GTC

Communication
Technologies Group
GTC

Communication
Technologies Group
40 50 60 70 80 90 100 110
bytes
10

20

30

40 50
ms

60

70
η=61/89=68%
.
.
.

Players

Local
agent

Access
router

Internet

Game Server
Players .
.
.

Player and
local agent

Access
router

Internet

Game Server
.
.
.

Players

Access
router and
local agent

Internet

Game Server
Central Game
Server
Game
Proxy

Game
Proxy

Game
Proxy
Players
Players

Wireless link
Multiplexer
TCM
Wireless link
.
.
.

TCM

Internet

Multiplexer
Wireless link

Players
Multiplexer

Players

TCM

Game Server
Native
traffic
...

Multiplexed
traffic . . .

PE

PE

PE

PE
...

...
Payload

Payload
Reduced Header

...

UDP
Reduced Header
IP

PPP Mux
PPP
L2TP
IP
L2TP PPP
header hea.

IP header

CH

PPP
Mux

Reduc.
header

Payload

MH

RH

P

...

PPP
Mux

Reduc.
header

Payload

MH

RH

P

Four IPv4/UDP client-to-server packets of Counter Strike
η=61/89=68%
One IPv4/TCM packet multiplexing four client-to-server Counter Strike packets
η=244/293=83%

saving
Game

BWRa IPv4 BWRa IPv6

Engine

E[P]

pps

Unreal T 2003

Unreal 2.0

29.5

25

62%

46%

Quake III

Id Tech 3

36.15

93

65%

50%

Quake II

Id Tech 2

37

26.38

66%

51%

Counter Strike

GoldSrc

41.09

24.65

68%

53%

Halo 2

Halo2

43.2

25

69%

54%
Original trace

Client to server

Server to client

Player 1 to N

Client to
server traffic
Player 1

Player 2

IP/UDP
headers
compressed

Multiplexed,
compressed
and tunneled

Player 1

Player 1 to N

Player 2
period
...

Player N

Not used

...

Player N
30%-35%
25%-30%
20%-25%
15%-20%
10%-15%
5%-10%
0%-5%

Bandwidth Saving

35%
30%
25%
20%
15%
10%

5%

50 ms
40 ms
30 ms
20 ms
period
10 ms

0%
20 19 18
17 16 15
14 13 12
11 10 9
8
number of players

7

6

5

4

3

2
Bandwidth Saving
35%
30%
25%

BS

20%
15%
20 players

10%

15 players
10 players

5%

5 players
0%
5

10

15

20

25
30
period (ms)

35

40

45

50
Bandwidth Saving
35%

Asymptote
30%
25%

BS

20%
15%
20 players

10%

15 players
10 players

5%

5 players
0%
5

10

15

20

25
30
period (ms)

35

40

45

50
Bandwidth Saving
35%
30%

BS

25%
20%
15%
T 10ms
T 20ms

10%

T 30ms
T 40 ms

5%

T 50ms
0%
2

3

4

5

6

7

8

9 10 11 12 13 14 15 16 17 18 19 20
number of players
5 players
10 players
15 players
20 players

Packet size in bytes
1400
1200

Packet size grows
linearly

bytes

1000
800
600
400
200
0
native

5

10

15

20

25
30
Period in ms

35

40

45

50
Average Retention Time
20 players

30

15 players
25

10 players
5 players

ms

20

15
10

Retention time is
half the period avg

5
0
5

15

25
Period in ms

35

45
Tretention Tprocess

Tqueue

Tnetwork

Tprocess

IP network
.
.
.

MUX

DEMUX

Game Server

Players
IP

TCM

IP
Bigger
packets

Bigger
period

Less
offered
traffic

Added
mux
delays

More
packet
loss

Less
packet
loss

Less
buffer
delay
Offline post-processing

Real Traffic in a testbed
Buffer

Network,
processing
delays

Game traffic
Background
Router
Traffic
Generation

Traffic
Capture

Traffic
Trace

Final
Results
One way delay for game traffic
200
delay native
180
delay mux 25ms
160

delay mux 50ms

OWD (ms)

140
120
100
80
60
40
20
0
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
One way delay for game traffic
200
delay native
180
delay mux 25ms
160

delay mux 50ms

OWD (ms)

140
120
100
80

25 + 5 ms
60

12,5 + 5 ms

40

Added mux
delays

20
0
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
One way delay for game traffic
200
delay native
180
delay mux 25ms
160

delay mux 50ms

Bandwidth saving
120kbps

OWD (ms)

140
120
100
80
60
40
20
0
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss for game traffic
18%
loss native
16%

loss mux 25ms

14%

loss mux 50ms

packet loss

12%
10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss for game traffic
18%
loss native
16%

loss mux 25ms

14%

loss mux 50ms

packet loss

12%
10%
8%

Bandwidth
saving

6%
4%
2%
0%
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss for game traffic
18%
loss native
16%

loss mux 25ms

14%

loss mux 50ms

Small saving
increase, but
double packet size

packet loss

12%
10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
One way delay for game traffic
200
delay native
180
delay mux 25ms
160

delay mux 50ms

OWD (ms)

140
120
100
80
60
40
20
0
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
One way delay for game traffic
200
delay native
180
delay mux 25ms
160

delay mux 50ms

Buffer delay
reduction

OWD (ms)

140
120
100
80
60
40

Added mux
delays

20
0
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
One way delay for game traffic
200
delay native

Bandwidth saving
120kbps

180
delay mux 25ms
160

delay mux 50ms

OWD (ms)

140
120
100
80
60
40
20
0
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss for game traffic
18%
loss native
16%

loss mux 25ms
14%

loss mux 50ms

packet loss

12%
10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss for game traffic
18%
loss native
16%

loss mux 25ms
14%

loss mux 50ms

packet loss

12%
10%
8%

Bandwidth
saving

6%
4%
2%
0%
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss for game traffic
18%
loss native
16%

loss mux 25ms
14%

loss mux 50ms

packet loss

12%

Big BG packets discarded
Native ones are small

10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss for game traffic
18%
loss native
16%

loss mux 25ms
14%

loss mux 50ms

Small saving increase but
double packet size

packet loss

12%
10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

850

Background traffic (kbps at link level)

900

950

1000
Packet loss Background Traffic
20%
native time limited

18%

mux 25ms time limited

mux 50ms time limited

16%

native high capacity

packet loss

14%

mux 25ms high capacity

mux 50ms high capacity

12%
10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

Background traffic (kbps at link level)

850

900

950

1000
Packet loss Background Traffic
20%
native time limited

18%

Buffer size does not
significantly modify BG
packet loss

mux 25ms time limited

mux 50ms time limited

16%

native high capacity

packet loss

14%

mux 25ms high capacity

mux 50ms high capacity

12%
10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

Background traffic (kbps at link level)

850

900

950

1000
Packet loss Background Traffic
20%
native time limited

18%

Bandwidth saving is
always beneficial for
BG traffic

mux 25ms time limited

mux 50ms time limited

16%

native high capacity

packet loss

14%

mux 25ms high capacity

mux 50ms high capacity

12%
10%
8%

6%
4%
2%
0%
500

550

600

650

700

750

800

Background traffic (kbps at link level)

850

900

950

1000
GTC

Communication
Technologies Group

Influence of the Router Buffer on Online Games Traffic Multiplexing