1. SIP over MANETs Introduction to SIP SIP vs MANETs Open Issues
Addressed Issues
State of Work
More work to do
References

2. Introduction to SIP (1) IETF RFC 3261 (replaces RFC 2543)
“The Session Initiation Protocol is an application-layer control (signaling) protocol for creating, modifying and terminating sessions with one or more participants”.
Can be used for voice, video, IM, gaming, etc…
Follows on HTTP
Text based messaging;
URIs – ex:

3. Introduction to SIP (2) User Agent User Agent Client (UAC)
End systems n
Send SIP requests l
User Agent Server (UAS) l
Redirect Server n
Listens for call requests n
“Network” server; redirects users to try other n
Prompts user or executes program to
server
determine response l
Proxy Server l
User Agent n
“Network Server” Proxies request to another n
UAC + UAS
server Can “fork” request to multiple servers,
creating a search tree l
Registrar n
receives registrations regarding current user
locations
SIP, Presence and IM

4. Introduction to SIP (3) SIP Architecture Request Response Media1 2 3 4 5 6 7 8 9 10 11 12
SIP Client
SIP Redirect
Server
SIP Proxy
(User Agent Server)
Location Service 13 14
SIP, Presence and IM

5. Introduction to SIP (4) SIP Message Syntax Many header fields from
http l
Payload contains a media
description
INVITE sip:
esumner
@dynamicsoft.com SIP/2.0
From: J. Rosenberg <sip:
jdrosen
@dynamicsoft.com> n
SDP -
Session
Subject: That pay increase
Description Protocol
To: Eric Sumner <sip:
esumner
@dynamicsoft.com>
Via: SIP/2.0/UDP pc13.dynamicsoft.com
Call -
ID:
Content -
type: application/
sdp
CSeq
: 4711 INVITE
Content -
Length: 187
v=0 o=
jdrosen
IN IP s= e=
jdrosen
@dynamicsoft.com
c=IN IP
t=0 0
m=audio 3456 RTP/AVP 0
SIP, Presence and IM

6. Introduction to SIP (5)

7. SIP vs MANETs SIP – Builds up on a well defined infrastructure
MANETs – No infrastructure

8. Open Issues (1)
How to deploy a real time service managed by SIP on a MANET?
Infrastructure
QoS
Cross layer interactions

9. Open Issues (2) Infrastructure Symmetric Asymmetric
All nodes have identical capabilities and responsibilities (e.g. UAC/S + Proxy + Registrar);
Asymmetric
different processing capacity of nodes (notebook vs PDA);
Speed of movement of nodes;
Battery life.

10. Open Issues (3) QoS policies may be applied through SIP
I can “create, modify and terminate” a session through SIP;
Can we modify parameters in order to get a better QoS?

11. Open Issues (4)
Which cross layer interactions are necessary for deploying Real Time services using SIP?

12. Addressed issues QoS: Cross-layering and Infrastructure:
Use CapProbe to trigger SIP to modify session parameters, measure jitter and delay with and without the option of session renegotiation;
Cross-layering and Infrastructure:
Deploy SIP on different routing schemes. Can hierarchical routing schemes simplify the deployment of SIP?

13. State of Work We have a SIP testbed in the lab (nist software);
The underlying routing protocol is AODV (University of Uppsala software);
I terminated the modifications of code for the client behaving as UAS, plan to finish the coding by the end of the week;
My partner is creating a JNI interface to CapProbe, for the moment it wont do probing from traffic packets.

14. More work to do
Test with other underlying routing protocols (e.g. DSR);
Test with video;
Design a more efficient infrastructure.

15. References IETF RFC 3261 J. Rosenberg tutorial on SIP, DynamicSoft
“Performance of Voice Traffic over Mobile Ad Hoc Netwok”, Kim et, Hankuk University, Korea
“Peer-to-Peer SIP-based Services over Wireless Ad Hoc Networks”, Banerjee, Acharaya, Das, UT Arlington, IBM Watson RC
3GPP Release 5 specification