1. NS2 (and possible directions for mobile routing simulation) Kevin Fall kfall@ee.lbl.gov
NS2 is the simulation vehicle for the VINT project:
USC/ISI: Deborah Estrin, Mark Handley, John Heideman, Ahmed Helmy, Polly Huang, Satish Kumar, Kannan Varadhan, Daniel Zappala
LBNL: Kevin Fall, Sally Floyd
UCBerkeley: Elan Amir, Steve McCanne
Xerox PARC: Lee Breslau, Scott Shenker
VINT is currently funded by DARPA through mid-1999

2. ns2 (UC Berkeley, LBNL) Discrete-event C++ simulation engine
scheduling, timers, packets
Split Otcl/C++ object “library”
protocol agents, links, nodes, classifiers, routing, error generators, traces, queuing, math support (random variables, integrals, etc)
separate visualization tool
used on many UNIXes, tested on Windows

3. Supported Components Protocols:
tcp (2modes + variants), udp, ip, rtp/rtcp, SRM, MAC, MAC
Routing
global topology map, classifiers
static unicast, dynamic unicast (distance-vector), multicast
Queueing and packet scheduling
FIFO/drop-tail, RED, CBQ, WRR, DRR, SFQ
Topology: nodes, links Failures: link errors/failures

4. Node Model

5. Link Model Links are simplex Implemented as compound objects:
queue, ttl checker (for IP), link delay element

6. Routing Interface Strategies: Parameters: static (precomputed)
session (on-demand static)
dynamic (DV for now)
Parameters:
link up/down times
costs
preference discriminator among routing protocols

7. Routing Architecture

8. Routing Architecture Components
RouteLogic:
global container for routing protocols, forwarding table and static routing implementation
rtObject:
per-node dispatcher to dynamic protocol agents
rtProto:
dynamic protocol agents (e.g. per-node)
rtPeer:
container for per-peer state, maintained by rtProto agents

9. Relevance to MANET Dynamic link failures can model topology changes
Modular routing structure easily extended
IP-style multicast routing already present
Rich multiprotocol simulation environment
New work: VINT “emulation” w/live networks

10. Additional Information
Web pages:
Mailing list:
“subscribe ns-users”