NSI

1. Network Service
Interface NSI 2.0
Jean C. F.
1

2. Outline
• Main Concepts
• NSI Services
• Connection Services
• Architecture
• NSI 2.0 and OSCARS 0.6
• NSI Topology
• NSI State Machines
• Questions
2

3. Main Concepts
• Network Service Interface v2.0 (NSI): Is an advanced interface
reservation between Request Agents and Provider Agents. Also NSI
defines a set of interactions and transactions beetween NSAs to realize a
Network Service
• Network Service Framework v2.0 (NSF): Describes an NSI messages
based platform capable of supporting a suite of Network Service such as
the Connection Service and the Topology Service
3

4. Main Concepts
Relation between main components of NSI
Network Service Interface NSI
1. Network
Service
Domain
2. Service
Termination
Points STP
3. Service
Demarcation
Point SDP
4. Network
Service
Agent NSA
5. Network
Resource
Management
NRM
4
Architecture Components

5. NSI Services
5
NSI Services
Connection
Services
(NSI-CS)
Topology
Services
(NSI-TS)
Discovery
Services
(NSI-DS)
Switching
Services
(NSI-SS)
Monitoring
Services
Protection
Services
Verification
Services
Can support

6. Connection Services
• Describes the protocol, state machine, architecture and associated processes and
environment in which software agents interact to deliver a Connection
• A connection is a point-to-point network circuit that can transit multiple networks
belonging to different providers.
Protocol that enables
• The reservation, creation, management and removal of Connections. To
ensure secure service delivery
• The NSI Connection Service incorporates authentication and authorization
mechanisms
Request
Agent
Provider
Agent
NSI
NSI Message
NSI Message
OSCARS OSCARS
6
Dominio A
Dominio Z

7. Connection Services
• The NSI is a web-service based API that operates between:
• A requester software agent and a provider software agent
• The full suite of NSI services allows an application or network provider to
request and manage circuit service instances
• The complete set of NSI services that is described in the:
• Network Services Framework v2.0 that describes an NSI message-
based send and receive platform capable of supporting services such
the connection service and transactions service
7

8. Connection Services
Process of Connection Service
• A reservation of a connection has properties such:
 A-point(start), Z-point (destiny) [mandatory]
 Start-time, End-time (optional)
 Bandwidth, Labels (optional)
• A reservation is made in two-phase
o First phase: availability is checked, if available resources are held
o Second phase: the requester either commit or abort a held reservation
• Two-phase is convenient when a requester requests resources from multiple providers, including
other resources such as computers and storages
• Timeout: If a requester does not commit a held reservation for a certain period of time, a provider can
timeout
• Modification of a reservation is supported:
o Currently, modification of start_time, end_time and bandwidth are supported
8

9. Architecture – NSA’s
• Network Service Agent (NSA): An NSA acts in one of two possible roles relative to a particular instance of an
NSI. When an NSA requests a service, it is called a Requester Agent (RA). When an NSA realizes a service, it
is called a Provider Agent (PA). A particular NSA may act in different roles at different interfaces
• Ultimate Request Agent (uRA): Is a Requester Agent that originate the service request
• Ultimate Provider Agent (uPA): Is a Provider Agent that has an associated NRM
• Aggregator: Is a NSA that has the responsability of aggregating the responses from each child NSA
Request
Agent NSI
NSI MessagesO
S
C
A
R
S
NSI Messages
NSI
Domain 1
Service Domain
NSI
9
Provider
Agent
Domain 2
Aggregator
O
S
C
A
R
S
Aggregator
Domain 3
Provider
Agent
O
S
C
A
R
S
Provider
Agent
Domain 4
O
S
C
A
R
S
NSI Messages NSI Messages
NSI MessagesNSI Messages

10. Architecture
Network Service Agents Interactions
10
NSA
(Ultimate) Requester
Agent
Coordinator
Message
Transport Layer NSA
Aggregator Agent
Coordinator
Message Transport
Layer
(Ultimate) Provider
Agent
Coordinator
Message Transport
Layer
Network Resource
Management
NSA
(Ultimate) Provider
Agent
Coordinator
Message Transport
Layer
Network Resource
Management
NSA
Aggregator Agent
Coordinator
Message Transport
Layer
NSA
(Ultimate) Provider
Agent
Coordinator
Message Transport
Layer
Network Resource
Management

11. Architecture - Abstraction of NSI, OSCARS
and MEICAN
MEICAN
DRIVER
PHP
OSCARS 0.5 OSCARS 0.6 OSCARS 0.6
Dominio 1
SSH/Telnet/SNMP
Web Service
Web Service Web Service
IDCP / NSIIDCP / NSI
Dominio 2
VLSR
VLSR
NARB
SNMP/Telnet SNMP/Telnet
DRAGON
SSH/TelnetSSH/Telnet
Dominio 3
VLSR
DRAGON
SSH/Telnet
SNMP/Telnet
uRA uPA uPA
OSCARS
Driver 0.5
Oscars
Bridge 0.6
Java
Oscars
Bridge 0.5
Aggregator
NSI Bridge
11

12. NSI 2.0 and OSCARS 0.6
OSCARS 0.6
SOAP API
OSCARS 0.5
SOAP API
NSI 2.0 API
(NSI Bridge)
Coordinator
Has the role of provide intelligent
messages and process
coordination
Other modules
13

13. NSI Topology
NSI defines Service Termination Point and Service Demaration Point in chain topology and
tree topology.
• Service Termination Points (STP)
• Are NSI topology objects that identify the edge point of a network in the intra-
network topology
• Service Demarcation Point (SDP)
• Are NSI topology objects that identify a group of two edge points in the end
between two networks
14
Network X Network Y
a b c d
STP a STP d
SDP
STP b / STP c

14. NSI Topology – Example of connection
managed by NSA chain and tree
Network Y
c d
Network X
a b
STP a
SDP
STP b / STP c
Network Z
f g
STP g
STP d / STP f
SDP
NSA - X
NSA - Y
NSA - Z
uRA
NSI Interface (NSA Chain)
NSI Interface (NSA Tree)
Network Connection 15

15. NSI States Machine
The NSI CS Network Service Agent has 3 logically distinct states machine (per reservation):
• Reservation State Machine (RSM)
o Manages the resource reservation process (i.e. scheduling and bookings)
o It’s instantiated as soon as first connection requests is received
• Provisioning State Machine (PSM)
o Supports the activation/deactivation of the data plane
o It’s instantiated as soon as the first “version” of the reservation is committed
o Decoupled from reservation process to delineate separation of concerns
• Life Cycle State Machine (LSM)
o Supports the termination of the reservation at any state/time
o It’s instantiated as soon as first connection requests is received
16

16. NSI States Machine – Messages
NSI CS offers seven
basic messages:
1. Reserve()
2. Provision()
3. Modify()
4. Release()
5. Terminate()
6. Query()
7. Notify()
17
Reserving
Scheduled
Provisioning
In-Service
Releasing
Released
Terminating
RA PA
Resv.rq
Resv.cf
Prov.rq
Prov.cf
Rel.rq
Rel.cf
Term.rq
Term.cf

17. NSI States Machine
Reservation State Machine
Reserve
Start
Reserve
Process
Reserve
held
Reserve
Timeout
Reserve
Aborting
Reserve
Failed
Reserve
Checking
Initial State
Transitional State
Stable State
18

18. NSI States Machine
Provision State Machine
Released
Provisioning
Provisioned
Releasing
Initial State
Transitional State
Stable State
19

19. NSI States Machine
Lifecycle State Machine
Created
Failed
Terminating
Initial State
Transitional State
Stable State
20
Passed End
Time
Terminated
Final State

20. NSI Topology
Network Markup Language - NML
The NML basic topology schema describes an information model for
computer networks. There are four types of classes:
1. Abstract classes (superclasses) with common attributes and parameters
(network object, service, group)
2. Network elements and functionalities (node, port, link, switching service,
adaptation service, deadaptation service) that inherit from abstract classes
3. Groups of elements and functionalities (topology, port group, link group,
bidirectional port, bidirectional link) that also inherit from abstract classes.
4. Supporting classes that include additional set of information (location,
lifetime), ordering feature (ordered list) or distributing network (label group)
21

21. Questions
1. What's changes has NSI 2.0 in relation of the protocolos like IDCP, DRAGON, VLSR and
NARB?
2. Does OSCARS 0.6 could works without NSI v2.0 protocol?
3. Does scheduled state works in NSI 2.0 such as in IDCP?
4. Does the bridge only support the CS NSI Service, or would it be capable to support new NSI
services?
5. Does NSI bridge support all the features of OSCARS 0.5 and OSCARS 0.6?
6. Does NSI Bridge has all the benefits of NSI 2.0 Connection Service?
7. Does firewall allows the communication between NSAs without issues?
8. Does the existing package like OSCARS 0.5 and 0.6 could integrated with the local provition
interface
22