1
Rules of Access List

• All deny statements have to be given First
• There should be at least one Permit statement
• An implicit deny blocks all traffic by default when
there is no match (an invisible statement).
• Can have one access-list per interface per direction.
(i.e.) Two access-list per interface, one in inbound
direction and one in outbound direction.
• Works in Sequential order
• Editing of access-lists is not possible (i.e) Selectively
adding or removing access-list statements is not
possible.

2
Standard ACL - Network Diagram

10.0.0.1/8
S0

HYD

1.2

S1
10.0.0.2/8

1.3

LAN - 192.168.1.0/24

is done Closest
is done Closest
to the
to the

11.0.0.1/8
S0

E0
192.168.1.150/24

1.1

Creation and
Creation and
Implementation
Implementation

2.1

Destination.
Destination.

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

1.1 & 1.2 should not communicate with 2.0 network
1.1 & 1.2 should not communicate with 2.0 network
3
How Standard ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

1.1 is accessing 2.1
1.1 is accessing 2.1

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

4
How Standard ACL Works ?

1.1

Source IP
192.168.1.1

2.1

Destination IP
192.168.2.1

access-list 1 deny 192.168.1.1 0.0.0.0
access-list 1 deny 192.168.1.2 0.0.0.0
access-list 1 permit any

5
How Standard ACL Works ?

1.1

Source IP
192.168.1.1

2.1

Destination IP
192.168.2.1

access-list 1 deny 192.168.1.1 0.0.0.0
access-list 1 deny 192.168.1.2 0.0.0.0
access-list 1 permit any

6
How Standard ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3
1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

1.3 is accessing 2.1
1.3 is accessing 2.1

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

7
How Standard ACL Works ?

1.1

Source IP
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 1 deny 192.168.1.1 0.0.0.0
access-list 1 deny 192.168.1.2 0.0.0.0
access-list 1 permit any

8

x
How Standard ACL Works ?

1.1

Source IP
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 1 deny 192.168.1.1 0.0.0.0
access-list 1 deny 192.168.1.2 0.0.0.0
access-list 1 permit any

9

x
How Standard ACL Works ?

1.1

Source IP
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 1 deny 192.168.1.1 0.0.0.0
access-list 1 deny 192.168.1.2 0.0.0.0
access-list 1 permit any

10
1.1

Source IP
192.168.1.1
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 1 deny 192.168.1.1 0.0.0.0
access-list 1 deny 192.168.1.2 0.0.0.0
access-list 1 permit any

11
Standard ACL - Network Diagram

10.0.0.1/8
S0

HYD

1.2

S1
10.0.0.2/8

1.3

LAN - 192.168.1.0/24

is done Closest
is done Closest
to the
to the

11.0.0.1/8
S0

E0
192.168.1.150/24

1.1

Creation and
Creation and
Implementation
Implementation

2.1

Destination.
Destination.

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

1.1 & 3.0 should not communicate with 2.0 network
1.1 & 3.0 should not communicate with 2.0 network
12
How Standard ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

1.1 is accessing 2.1
1.1 is accessing 2.1

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

13
How Standard ACL Works ?

1.1

Source IP
192.168.1.1

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0
access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

14
How Standard ACL Works ?

1.1

Source IP
192.168.1.1

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0
access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

15
How Standard ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3
1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

1.3 is accessing 2.1
1.3 is accessing 2.1

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

16
How Standard ACL Works ?

1.3

Source IP
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0

x

access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

17
How Standard ACL Works ?

1.3

Source IP
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0

access-list 5 deny 192.168.3.0 0.0.0.255 x
access-list 5 permit any

18
How Standard ACL Works ?

1.3

Source IP
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0
access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

19
1.3

Source IP
192.168.1.1
192.168.1.3

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0
access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

20
How Standard ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

3.1 is accessing 2.1
3.1 is accessing 2.1

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

21
How Standard ACL Works ?

3.1

Source IP
192.168.3.1

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0

x

access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

22
How Standard ACL Works ?

3.1

Source IP
192.168.3.1

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0
access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

23
How Standard ACL Works ?

3.1

Source IP
192.168.3.1

2.1

Destination IP
192.168.2.1

access-list 5 deny 192.168.1.1 0.0.0.0
access-list 5 deny 192.168.3.0 0.0.0.255
access-list 5 permit any

24
Extended ACL - Network Diagram
Creation and
Creation and
Implementation
Implementation
10.0.0.1/8
S0

HYD

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3

LAN - 192.168.1.0/24

is done Closest
is done Closest
to the Source.
to the Source.

11.0.0.1/8
S0

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

2.0 should not access with 3.1 (Web Service)
2.0 should not access with 3.1 (Web Service)
25
How Extended ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

2.1 is accessing 3.1 -- Web Service
2.1 is accessing 3.1 Web Service
26
How Extended ACL Works ?

2.1

Source IP
192.168.2.1
Destination IP
192.168.3.1
Port - 80

3.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

27
How Extended ACL Works ?

2.1

Source IP
192.168.2.1
Destination IP
192.168.3.1
Port - 80

3.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

28
How Extended ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

2.1 is accessing 3.1 – Telnet Service
2.1 is accessing 3.1 – Telnet Service
29
How Extended ACL Works ?

2.1

Source IP
192.168.2.1
Destination IP
192.168.3.1
Port - 23

3.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

30

x
How Extended ACL Works ?

2.1

Source IP
192.168.2.1
Destination IP
192.168.3.1
Port - 23

3.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

31
How Extended ACL Works ?

2.1

Source IP
192.168.1.1
192.168.2.1
Destination IP
192.168.3.1
Port - 23

3.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

32
How Extended ACL Works ?

10.0.0.1/8
S0

HYD

11.0.0.1/8
S0

S1
10.0.0.2/8

E0
192.168.1.150/24

1.1

1.2

1.3

LAN - 192.168.1.0/24

2.1

CHE

S1
11.0.0.2/8

E0
192.168.2.150/24

2.2

2.3

LAN - 192.168.2.0/24

3.1

BAN

E0
192.168.3.150/2

3.2

3.3

LAN - 192.168.3.0/24

2.1 is accessing 1.1 -- Web Service
2.1 is accessing 1.1 Web Service
33
How Extended ACL Works ?

2.1

Source IP
192.168.2.1
Destination IP
192.168.1.1
192.168.1.1
Port - 80

1.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

34

x
How Extended ACL Works ?

2.1

Source IP
192.168.2.1
Destination IP
192.168.1.1
Port - 80

1.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

35
How Extended ACL Works ?

2.1

Source IP
192.168.1.1
192.168.2.1
Destination IP
192.168.1.1
Port - 80

1.1

access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80
access-list 101 permit ip any any

36
Named Access List

• Access-lists are identified using Names
rather than Numbers.
• Names are Case-Sensitive
• No limitation of Numbers here.
• One Main Advantage is Editing of ACL is Possible (i.e)
Removing a specific statement from the ACL is
possible.
(IOS version 11.2 or later allows Named ACL)

37
Standard Named Access List

Creation of Standard Named Access List
Creation of Standard Named Access List
Router(config)# ip access-list standard <name>
Router(config)# ip access-list standard <name>
Router(config-std-nacl)# <permit/deny> <source address>
Router(config-std-nacl)# <permit/deny> <source address>
<source wildcard mask>
<source wildcard mask>

Implementation of Standard Named Access List
Implementation of Standard Named Access List
Router(config)#interface <interface type><interface no>
Router(config)#interface <interface type><interface no>
Router(config-if)#ip access-group <name> <out/in>
Router(config-if)#ip access-group <name> <out/in>

38
Extended Named Access List

Creation of Extended Named Access List
Creation of Extended Named Access List
Router(config)# ip access-list extended <name>
Router(config)# ip access-list extended <name>
Router(config-ext-nacl)# <permit/deny> <protocol>
Router(config-ext-nacl)# <permit/deny> <protocol>
<source address> <source wildcard mask> <destination
<source address> <source wildcard mask> <destination
address> < destination wildcard mask> <operator>
address> < destination wildcard mask> <operator>
<service>
<service>
Implementation of Extended Named Access List
Implementation of Extended Named Access List
Router(config)#interface <interface type><interface no>
Router(config)#interface <interface type><interface no>
Router(config-if)#ip access-group <name> <out/in>
Router(config-if)#ip access-group <name> <out/in>

39
40
Microsoft Windows 2000 [Version 5.00.2195]
(C) Copyright 1985-2000 Microsoft Corp.
C:> telnet 192.168.1.150
Connecting .....
================================
Welcome to Hyderabad Router
================================
User Access Verification
password : ****
Hyderabad> enable
password : ****
Hyderabad# show ip route
Gateway of last resort is not set
C
10.0.0.0/8 is directly connected, Serial0
R
11.0.0.0/8 [120/1] via 10.0.0.2, 00:00:25, Serial0
C
192.168.1.0/24 is directly connected, Ethernet0
R
192.168.2.0/24 [120/1] via 10.0.0.2, 00:00:25, Serial0
R
192.168.3.0/24 [120/2] via 10.0.0.2, 00:00:25, Serial0
Hyderabad#

41
Microsoft Windows 2000 [Version 5.00.2195]
(C) Copyright 1985-2000 Microsoft Corp.
C:> telnet 192.168.2.150
Connecting .....
================================
Welcome to Chennai Router
================================
User Access Verification
password : ****
Chennai> enable
password : ****
Chennai# show ip route
Gateway of last resort is not set
C
10.0.0.0/8 is directly connected, Serial1
C
11.0.0.0/8 is directly connected, Serial0
R
192.168.1.0/24 [120/1] via 10.0.0.1, 00:00:01, Serial1
C
192.168.2.0/24 is directly connected, Ethernet0
R
192.168.3.0/24 [120/1] via 11.0.0.2, 00:00:12, Serial0
Chennai#

42
Microsoft Windows 2000 [Version 5.00.2195]
(C) Copyright 1985-2000 Microsoft Corp.
C:> telnet 192.168.3.150
Connecting .....
================================
Welcome to Banglore Router
================================
User Access Verification
password : ****
Banglore> enable
password : ****
Banglore# show ip route
Gateway of last resort is not set
R
10.0.0.0/8 [120/1] via 11.0.0.1, 00:00:04, Serial1
C
11.0.0.0/8 is directly connected, Serial1
R
192.168.1.0/24 [120/2] via 11.0.0.1, 00:00:04, Serial1
R
192.168.2.0/24 [120/1] via 11.0.0.1, 00:00:04, Serial1
C
192.168.3.0/24 is directly connected, Ethernet0
Banglore#

43
Microsoft Windows 2000 [Version 5.00.2195]
(C) Copyright 1985-2000 Microsoft Corp.
C:> telnet 192.168.2.150
Connecting .....
================================
Welcome to Chennai Router
================================
User Access Verification
password : ****
Chennai> enable
password : ****
Chennai# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Chennai(config)# interface serial 1
Chennai(config-if)# ip address 10.0.0.2 255.0.0.0
Chennai(config-if)# no shut
Chennai(config-if)# encapsulation hdlc
Chennai(config-if)# interface serial 0
Chennai(config-if)# ip address 11.0.0.1 255.0.0.0
Chennai(config-if)# no shut
Chennai(config-if)# encapsulation hdlc

44
Chennai# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Chennai(config)# access-list 1 deny 192.168.1.1 0.0.0.0
Chennai(config)# access-list 1 deny 192.168.1.2 0.0.0.0
Chennai(config)# access-list 1 permit any
Creation of Standard Access List
Creation of Standard Access List
Chennai(config)# interface ethernet 0
Router(config)# access-list out
Chennai(config-if)# ip access-group 1 <acl no> <permit/deny>
Router(config)# access-list <acl no> <permit/deny>
<source address> <source wildcard mask>
<source address> <source wildcard mask>
Chennai(config-if)#
Implementation of Standard Access List
Implementation of Standard Access List
Router(config)#interface <interface type><interface no>
Router(config)#interface <interface type><interface no>
Router(config-if)#ip access-group <number> <out/in>
Router(config-if)#ip access-group <number> <out/in>

45
Chennai# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Chennai(config)# access-list 1 deny 192.168.1.1 0.0.0.0
Chennai(config)# access-list 1 deny 192.168.1.2 0.0.0.0
Chennai(config)# access-list 1 permit any
Chennai(config)# interface ethernet 0
Chennai(config-if)# ip access-group 1 out
Chennai(config-if)# ^Z
Chennai# show ip access-list
Standard IP access list 1
deny
192.168.1.1
deny
192.168.1.2
permit any
Chennai#

46
Chennai# show ip int e0
Ethernet0 is up, line protocol is up
Internet address is 192.168.2.150/24
Broadcast address is 255.255.255.255
Address determined by non-volatile memory
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is enabled
Multicast reserved groups joined: 224.0.0.9
Outgoing access list is 1
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is enabled
IP fast switching on the same interface is disabled
IP multicast fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
Probe proxy name replies are disabled
Gateway Discovery is disabled
Policy routing is disabled
Network address translation is disabled

Chennai#

47
Chennai# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Chennai(config)# access-list 5 deny 192.168.1.1 0.0.0.0
Chennai(config)# access-list 5 deny 192.168.3.0 0.0.0.255
Chennai(config)# access-list 5 permit any
Chennai(config)# interface ethernet 0
Chennai(config-if)# ip access-group 5 out
Chennai(config-if)# ^Z
Chennai# show ip access-list
Standard
deny
deny
permit
Chennai#

IP access list 5
192.168.1.1
192.168.3.0
any

48
Chennai# show ip int e0
Ethernet0 is up, line protocol is up
Internet address is 192.168.2.150/24
Broadcast address is 255.255.255.255
Address determined by non-volatile memory
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is enabled
Multicast reserved groups joined: 224.0.0.9
Outgoing access list is 5
Inbound access list is not set
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is enabled
IP fast switching on the same interface is disabled
IP multicast fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
Probe proxy name replies are disabled
Gateway Discovery is disabled
Policy routing is disabled
Network address translation is disabled

Chennai#

49
Chennai# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Chennai(config)# access-list 5 deny 192.168.1.1 0.0.0.0
Chennai(config)# access-list 5 deny 192.168.3.0 0.0.0.255
Chennai(config)# access-list 5 permit any
Creation of Standard Access List
Creation of Standard Access List
Chennai(config)# interface ethernet 0
Router(config)# access-list out
Chennai(config-if)# ip access-group 5 <acl no> <permit/deny>
Router(config)# access-list <acl no> <permit/deny>
<source address> <source wildcard mask>
<source address> <source wildcard mask>
Chennai(config-if)#
Implementation of Standard Access List
Implementation of Standard Access List
Router(config)#interface <interface type><interface no>
Router(config)#interface <interface type><interface no>
Router(config-if)#ip access-group <number> <out/in>
Router(config-if)#ip access-group <number> <out/in>

50
Chennai# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Chennai(config)# access-list 101 deny tcp 192.168.2.0
0.0.0.255 192.168.3.1 0.0.0.0 eq 80
Chennai(config)# access-list 101 Extended Access List
permit ip any any
Creation of Extended Access List
Creation of
Chennai(config)# interface ethernet 0
Router(config)# access-list <acl no> <permit/deny>
Router(config)# access-list <acl no> <permit/deny>
Chennai(config-if)# ip access-group 101 <source wildcard mask>
<protocol> <source address> in
<protocol> <source address> <source wildcard mask>
Chennai(config-if)#
<destination address> < destination wildcard mask>
<destination address> < destination wildcard mask>
<operator> <service>
Implementation of Extended Access List
<operator> <service> of Extended Access List
Implementation
Router(config)#interface <interface type><interface no>
Router(config)#interface <interface type><interface no>
Router(config-if)#ip access-group <number> <out/in>
Router(config-if)#ip access-group <number> <out/in>

51
Chennai# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Chennai(config)# access-list 101 deny tcp 192.168.2.0
0.0.0.255 192.168.3.1 0.0.0.0 eq 80
Chennai(config)# access-list 101 permit ip any any
Chennai(config)# interface ethernet 0
Chennai(config-if)# ip access-group 101 in
Chennai(config-if)# ^Z
Chennai# show ip access-list
Extended IP access list 101
deny
tcp 192.168.2.0 0.0.0.255 host 192.168.3.1 eq www
permit ip any any
Chennai#

52
Chennai# show ip int e0
Ethernet0 is up, line protocol is up
Internet address is 192.168.2.150/24
Broadcast address is 255.255.255.255
Address determined by non-volatile memory
MTU is 1500 bytes
Helper address is not set
Directed broadcast forwarding is enabled
Multicast reserved groups joined: 224.0.0.9
Outgoing access list is not set
Inbound access list is 101
Proxy ARP is enabled
Security level is default
Split horizon is enabled
ICMP redirects are always sent
ICMP unreachables are always sent
ICMP mask replies are never sent
IP fast switching is enabled
IP fast switching on the same interface is disabled
IP multicast fast switching is disabled
Router Discovery is disabled
IP output packet accounting is disabled
IP access violation accounting is disabled
TCP/IP header compression is disabled
Probe proxy name replies are disabled
Gateway Discovery is disabled
Policy routing is disabled
Network address translation is disabled

Chennai#

53

Access Control List 1

  • 1.
  • 2.
    Rules of AccessList • All deny statements have to be given First • There should be at least one Permit statement • An implicit deny blocks all traffic by default when there is no match (an invisible statement). • Can have one access-list per interface per direction. (i.e.) Two access-list per interface, one in inbound direction and one in outbound direction. • Works in Sequential order • Editing of access-lists is not possible (i.e) Selectively adding or removing access-list statements is not possible. 2
  • 3.
    Standard ACL -Network Diagram 10.0.0.1/8 S0 HYD 1.2 S1 10.0.0.2/8 1.3 LAN - 192.168.1.0/24 is done Closest is done Closest to the to the 11.0.0.1/8 S0 E0 192.168.1.150/24 1.1 Creation and Creation and Implementation Implementation 2.1 Destination. Destination. CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 1.1 & 1.2 should not communicate with 2.0 network 1.1 & 1.2 should not communicate with 2.0 network 3
  • 4.
    How Standard ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 1.1 is accessing 2.1 1.1 is accessing 2.1 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 4
  • 5.
    How Standard ACLWorks ? 1.1 Source IP 192.168.1.1 2.1 Destination IP 192.168.2.1 access-list 1 deny 192.168.1.1 0.0.0.0 access-list 1 deny 192.168.1.2 0.0.0.0 access-list 1 permit any 5
  • 6.
    How Standard ACLWorks ? 1.1 Source IP 192.168.1.1 2.1 Destination IP 192.168.2.1 access-list 1 deny 192.168.1.1 0.0.0.0 access-list 1 deny 192.168.1.2 0.0.0.0 access-list 1 permit any 6
  • 7.
    How Standard ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 1.3 is accessing 2.1 1.3 is accessing 2.1 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 7
  • 8.
    How Standard ACLWorks ? 1.1 Source IP 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list 1 deny 192.168.1.1 0.0.0.0 access-list 1 deny 192.168.1.2 0.0.0.0 access-list 1 permit any 8 x
  • 9.
    How Standard ACLWorks ? 1.1 Source IP 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list 1 deny 192.168.1.1 0.0.0.0 access-list 1 deny 192.168.1.2 0.0.0.0 access-list 1 permit any 9 x
  • 10.
    How Standard ACLWorks ? 1.1 Source IP 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list 1 deny 192.168.1.1 0.0.0.0 access-list 1 deny 192.168.1.2 0.0.0.0 access-list 1 permit any 10
  • 11.
    1.1 Source IP 192.168.1.1 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list1 deny 192.168.1.1 0.0.0.0 access-list 1 deny 192.168.1.2 0.0.0.0 access-list 1 permit any 11
  • 12.
    Standard ACL -Network Diagram 10.0.0.1/8 S0 HYD 1.2 S1 10.0.0.2/8 1.3 LAN - 192.168.1.0/24 is done Closest is done Closest to the to the 11.0.0.1/8 S0 E0 192.168.1.150/24 1.1 Creation and Creation and Implementation Implementation 2.1 Destination. Destination. CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 1.1 & 3.0 should not communicate with 2.0 network 1.1 & 3.0 should not communicate with 2.0 network 12
  • 13.
    How Standard ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 1.1 is accessing 2.1 1.1 is accessing 2.1 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 13
  • 14.
    How Standard ACLWorks ? 1.1 Source IP 192.168.1.1 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 14
  • 15.
    How Standard ACLWorks ? 1.1 Source IP 192.168.1.1 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 15
  • 16.
    How Standard ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 1.3 is accessing 2.1 1.3 is accessing 2.1 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 16
  • 17.
    How Standard ACLWorks ? 1.3 Source IP 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 x access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 17
  • 18.
    How Standard ACLWorks ? 1.3 Source IP 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 access-list 5 deny 192.168.3.0 0.0.0.255 x access-list 5 permit any 18
  • 19.
    How Standard ACLWorks ? 1.3 Source IP 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 19
  • 20.
    1.3 Source IP 192.168.1.1 192.168.1.3 2.1 Destination IP 192.168.2.1 access-list5 deny 192.168.1.1 0.0.0.0 access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 20
  • 21.
    How Standard ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 3.1 is accessing 2.1 3.1 is accessing 2.1 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 21
  • 22.
    How Standard ACLWorks ? 3.1 Source IP 192.168.3.1 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 x access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 22
  • 23.
    How Standard ACLWorks ? 3.1 Source IP 192.168.3.1 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 23
  • 24.
    How Standard ACLWorks ? 3.1 Source IP 192.168.3.1 2.1 Destination IP 192.168.2.1 access-list 5 deny 192.168.1.1 0.0.0.0 access-list 5 deny 192.168.3.0 0.0.0.255 access-list 5 permit any 24
  • 25.
    Extended ACL -Network Diagram Creation and Creation and Implementation Implementation 10.0.0.1/8 S0 HYD S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 LAN - 192.168.1.0/24 is done Closest is done Closest to the Source. to the Source. 11.0.0.1/8 S0 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 2.0 should not access with 3.1 (Web Service) 2.0 should not access with 3.1 (Web Service) 25
  • 26.
    How Extended ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 2.1 is accessing 3.1 -- Web Service 2.1 is accessing 3.1 Web Service 26
  • 27.
    How Extended ACLWorks ? 2.1 Source IP 192.168.2.1 Destination IP 192.168.3.1 Port - 80 3.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 27
  • 28.
    How Extended ACLWorks ? 2.1 Source IP 192.168.2.1 Destination IP 192.168.3.1 Port - 80 3.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 28
  • 29.
    How Extended ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 2.1 is accessing 3.1 – Telnet Service 2.1 is accessing 3.1 – Telnet Service 29
  • 30.
    How Extended ACLWorks ? 2.1 Source IP 192.168.2.1 Destination IP 192.168.3.1 Port - 23 3.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 30 x
  • 31.
    How Extended ACLWorks ? 2.1 Source IP 192.168.2.1 Destination IP 192.168.3.1 Port - 23 3.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 31
  • 32.
    How Extended ACLWorks ? 2.1 Source IP 192.168.1.1 192.168.2.1 Destination IP 192.168.3.1 Port - 23 3.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 32
  • 33.
    How Extended ACLWorks ? 10.0.0.1/8 S0 HYD 11.0.0.1/8 S0 S1 10.0.0.2/8 E0 192.168.1.150/24 1.1 1.2 1.3 LAN - 192.168.1.0/24 2.1 CHE S1 11.0.0.2/8 E0 192.168.2.150/24 2.2 2.3 LAN - 192.168.2.0/24 3.1 BAN E0 192.168.3.150/2 3.2 3.3 LAN - 192.168.3.0/24 2.1 is accessing 1.1 -- Web Service 2.1 is accessing 1.1 Web Service 33
  • 34.
    How Extended ACLWorks ? 2.1 Source IP 192.168.2.1 Destination IP 192.168.1.1 192.168.1.1 Port - 80 1.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 34 x
  • 35.
    How Extended ACLWorks ? 2.1 Source IP 192.168.2.1 Destination IP 192.168.1.1 Port - 80 1.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 35
  • 36.
    How Extended ACLWorks ? 2.1 Source IP 192.168.1.1 192.168.2.1 Destination IP 192.168.1.1 Port - 80 1.1 access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 access-list 101 permit ip any any 36
  • 37.
    Named Access List •Access-lists are identified using Names rather than Numbers. • Names are Case-Sensitive • No limitation of Numbers here. • One Main Advantage is Editing of ACL is Possible (i.e) Removing a specific statement from the ACL is possible. (IOS version 11.2 or later allows Named ACL) 37
  • 38.
    Standard Named AccessList Creation of Standard Named Access List Creation of Standard Named Access List Router(config)# ip access-list standard <name> Router(config)# ip access-list standard <name> Router(config-std-nacl)# <permit/deny> <source address> Router(config-std-nacl)# <permit/deny> <source address> <source wildcard mask> <source wildcard mask> Implementation of Standard Named Access List Implementation of Standard Named Access List Router(config)#interface <interface type><interface no> Router(config)#interface <interface type><interface no> Router(config-if)#ip access-group <name> <out/in> Router(config-if)#ip access-group <name> <out/in> 38
  • 39.
    Extended Named AccessList Creation of Extended Named Access List Creation of Extended Named Access List Router(config)# ip access-list extended <name> Router(config)# ip access-list extended <name> Router(config-ext-nacl)# <permit/deny> <protocol> Router(config-ext-nacl)# <permit/deny> <protocol> <source address> <source wildcard mask> <destination <source address> <source wildcard mask> <destination address> < destination wildcard mask> <operator> address> < destination wildcard mask> <operator> <service> <service> Implementation of Extended Named Access List Implementation of Extended Named Access List Router(config)#interface <interface type><interface no> Router(config)#interface <interface type><interface no> Router(config-if)#ip access-group <name> <out/in> Router(config-if)#ip access-group <name> <out/in> 39
  • 40.
  • 41.
    Microsoft Windows 2000[Version 5.00.2195] (C) Copyright 1985-2000 Microsoft Corp. C:> telnet 192.168.1.150 Connecting ..... ================================ Welcome to Hyderabad Router ================================ User Access Verification password : **** Hyderabad> enable password : **** Hyderabad# show ip route Gateway of last resort is not set C 10.0.0.0/8 is directly connected, Serial0 R 11.0.0.0/8 [120/1] via 10.0.0.2, 00:00:25, Serial0 C 192.168.1.0/24 is directly connected, Ethernet0 R 192.168.2.0/24 [120/1] via 10.0.0.2, 00:00:25, Serial0 R 192.168.3.0/24 [120/2] via 10.0.0.2, 00:00:25, Serial0 Hyderabad# 41
  • 42.
    Microsoft Windows 2000[Version 5.00.2195] (C) Copyright 1985-2000 Microsoft Corp. C:> telnet 192.168.2.150 Connecting ..... ================================ Welcome to Chennai Router ================================ User Access Verification password : **** Chennai> enable password : **** Chennai# show ip route Gateway of last resort is not set C 10.0.0.0/8 is directly connected, Serial1 C 11.0.0.0/8 is directly connected, Serial0 R 192.168.1.0/24 [120/1] via 10.0.0.1, 00:00:01, Serial1 C 192.168.2.0/24 is directly connected, Ethernet0 R 192.168.3.0/24 [120/1] via 11.0.0.2, 00:00:12, Serial0 Chennai# 42
  • 43.
    Microsoft Windows 2000[Version 5.00.2195] (C) Copyright 1985-2000 Microsoft Corp. C:> telnet 192.168.3.150 Connecting ..... ================================ Welcome to Banglore Router ================================ User Access Verification password : **** Banglore> enable password : **** Banglore# show ip route Gateway of last resort is not set R 10.0.0.0/8 [120/1] via 11.0.0.1, 00:00:04, Serial1 C 11.0.0.0/8 is directly connected, Serial1 R 192.168.1.0/24 [120/2] via 11.0.0.1, 00:00:04, Serial1 R 192.168.2.0/24 [120/1] via 11.0.0.1, 00:00:04, Serial1 C 192.168.3.0/24 is directly connected, Ethernet0 Banglore# 43
  • 44.
    Microsoft Windows 2000[Version 5.00.2195] (C) Copyright 1985-2000 Microsoft Corp. C:> telnet 192.168.2.150 Connecting ..... ================================ Welcome to Chennai Router ================================ User Access Verification password : **** Chennai> enable password : **** Chennai# configure terminal Enter configuration commands, one per line. End with CNTL/Z. Chennai(config)# interface serial 1 Chennai(config-if)# ip address 10.0.0.2 255.0.0.0 Chennai(config-if)# no shut Chennai(config-if)# encapsulation hdlc Chennai(config-if)# interface serial 0 Chennai(config-if)# ip address 11.0.0.1 255.0.0.0 Chennai(config-if)# no shut Chennai(config-if)# encapsulation hdlc 44
  • 45.
    Chennai# configure terminal Enterconfiguration commands, one per line. End with CNTL/Z. Chennai(config)# access-list 1 deny 192.168.1.1 0.0.0.0 Chennai(config)# access-list 1 deny 192.168.1.2 0.0.0.0 Chennai(config)# access-list 1 permit any Creation of Standard Access List Creation of Standard Access List Chennai(config)# interface ethernet 0 Router(config)# access-list out Chennai(config-if)# ip access-group 1 <acl no> <permit/deny> Router(config)# access-list <acl no> <permit/deny> <source address> <source wildcard mask> <source address> <source wildcard mask> Chennai(config-if)# Implementation of Standard Access List Implementation of Standard Access List Router(config)#interface <interface type><interface no> Router(config)#interface <interface type><interface no> Router(config-if)#ip access-group <number> <out/in> Router(config-if)#ip access-group <number> <out/in> 45
  • 46.
    Chennai# configure terminal Enterconfiguration commands, one per line. End with CNTL/Z. Chennai(config)# access-list 1 deny 192.168.1.1 0.0.0.0 Chennai(config)# access-list 1 deny 192.168.1.2 0.0.0.0 Chennai(config)# access-list 1 permit any Chennai(config)# interface ethernet 0 Chennai(config-if)# ip access-group 1 out Chennai(config-if)# ^Z Chennai# show ip access-list Standard IP access list 1 deny 192.168.1.1 deny 192.168.1.2 permit any Chennai# 46
  • 47.
    Chennai# show ipint e0 Ethernet0 is up, line protocol is up Internet address is 192.168.2.150/24 Broadcast address is 255.255.255.255 Address determined by non-volatile memory MTU is 1500 bytes Helper address is not set Directed broadcast forwarding is enabled Multicast reserved groups joined: 224.0.0.9 Outgoing access list is 1 Inbound access list is not set Proxy ARP is enabled Security level is default Split horizon is enabled ICMP redirects are always sent ICMP unreachables are always sent ICMP mask replies are never sent IP fast switching is enabled IP fast switching on the same interface is disabled IP multicast fast switching is disabled Router Discovery is disabled IP output packet accounting is disabled IP access violation accounting is disabled TCP/IP header compression is disabled Probe proxy name replies are disabled Gateway Discovery is disabled Policy routing is disabled Network address translation is disabled Chennai# 47
  • 48.
    Chennai# configure terminal Enterconfiguration commands, one per line. End with CNTL/Z. Chennai(config)# access-list 5 deny 192.168.1.1 0.0.0.0 Chennai(config)# access-list 5 deny 192.168.3.0 0.0.0.255 Chennai(config)# access-list 5 permit any Chennai(config)# interface ethernet 0 Chennai(config-if)# ip access-group 5 out Chennai(config-if)# ^Z Chennai# show ip access-list Standard deny deny permit Chennai# IP access list 5 192.168.1.1 192.168.3.0 any 48
  • 49.
    Chennai# show ipint e0 Ethernet0 is up, line protocol is up Internet address is 192.168.2.150/24 Broadcast address is 255.255.255.255 Address determined by non-volatile memory MTU is 1500 bytes Helper address is not set Directed broadcast forwarding is enabled Multicast reserved groups joined: 224.0.0.9 Outgoing access list is 5 Inbound access list is not set Proxy ARP is enabled Security level is default Split horizon is enabled ICMP redirects are always sent ICMP unreachables are always sent ICMP mask replies are never sent IP fast switching is enabled IP fast switching on the same interface is disabled IP multicast fast switching is disabled Router Discovery is disabled IP output packet accounting is disabled IP access violation accounting is disabled TCP/IP header compression is disabled Probe proxy name replies are disabled Gateway Discovery is disabled Policy routing is disabled Network address translation is disabled Chennai# 49
  • 50.
    Chennai# configure terminal Enterconfiguration commands, one per line. End with CNTL/Z. Chennai(config)# access-list 5 deny 192.168.1.1 0.0.0.0 Chennai(config)# access-list 5 deny 192.168.3.0 0.0.0.255 Chennai(config)# access-list 5 permit any Creation of Standard Access List Creation of Standard Access List Chennai(config)# interface ethernet 0 Router(config)# access-list out Chennai(config-if)# ip access-group 5 <acl no> <permit/deny> Router(config)# access-list <acl no> <permit/deny> <source address> <source wildcard mask> <source address> <source wildcard mask> Chennai(config-if)# Implementation of Standard Access List Implementation of Standard Access List Router(config)#interface <interface type><interface no> Router(config)#interface <interface type><interface no> Router(config-if)#ip access-group <number> <out/in> Router(config-if)#ip access-group <number> <out/in> 50
  • 51.
    Chennai# configure terminal Enterconfiguration commands, one per line. End with CNTL/Z. Chennai(config)# access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 Chennai(config)# access-list 101 Extended Access List permit ip any any Creation of Extended Access List Creation of Chennai(config)# interface ethernet 0 Router(config)# access-list <acl no> <permit/deny> Router(config)# access-list <acl no> <permit/deny> Chennai(config-if)# ip access-group 101 <source wildcard mask> <protocol> <source address> in <protocol> <source address> <source wildcard mask> Chennai(config-if)# <destination address> < destination wildcard mask> <destination address> < destination wildcard mask> <operator> <service> Implementation of Extended Access List <operator> <service> of Extended Access List Implementation Router(config)#interface <interface type><interface no> Router(config)#interface <interface type><interface no> Router(config-if)#ip access-group <number> <out/in> Router(config-if)#ip access-group <number> <out/in> 51
  • 52.
    Chennai# configure terminal Enterconfiguration commands, one per line. End with CNTL/Z. Chennai(config)# access-list 101 deny tcp 192.168.2.0 0.0.0.255 192.168.3.1 0.0.0.0 eq 80 Chennai(config)# access-list 101 permit ip any any Chennai(config)# interface ethernet 0 Chennai(config-if)# ip access-group 101 in Chennai(config-if)# ^Z Chennai# show ip access-list Extended IP access list 101 deny tcp 192.168.2.0 0.0.0.255 host 192.168.3.1 eq www permit ip any any Chennai# 52
  • 53.
    Chennai# show ipint e0 Ethernet0 is up, line protocol is up Internet address is 192.168.2.150/24 Broadcast address is 255.255.255.255 Address determined by non-volatile memory MTU is 1500 bytes Helper address is not set Directed broadcast forwarding is enabled Multicast reserved groups joined: 224.0.0.9 Outgoing access list is not set Inbound access list is 101 Proxy ARP is enabled Security level is default Split horizon is enabled ICMP redirects are always sent ICMP unreachables are always sent ICMP mask replies are never sent IP fast switching is enabled IP fast switching on the same interface is disabled IP multicast fast switching is disabled Router Discovery is disabled IP output packet accounting is disabled IP access violation accounting is disabled TCP/IP header compression is disabled Probe proxy name replies are disabled Gateway Discovery is disabled Policy routing is disabled Network address translation is disabled Chennai# 53