[Ns-announce] ns-2.26 release announcement
Fri Feb 28 11:45:03 2003
We are happy to announce that a new release of ns (version 2.26) is now
available. This release of ns also comes with new releases of nam
(v1.9), tclcl(v1.0b13) and ns-allinone(v2.26) pkg. The
ns/nam release has many new features/modules as well as several bug-fixes
which are listed in brief below.
The tarfiles for ns-allinone, ns and nam src codes are called as
You can download these latest release versions
(by HTTP) from http://www.isi.edu/nsnam/dist/ and
by FTP from ftp://ftp.isi.edu/nsnam/.
The ns-build page at http://www.isi.edu/nsnam/ns/ns-build.html
should be updated to show the release by midnight today.
Please send all your comments and bug-reports to firstname.lastname@example.org
New version numbering for ns and nam
As of this release we are changing the ns and nam version numbering
scheme from 2.1b10 (major.minor alpha/beta increment) to simply 2.26
(major.minor). Unlike typical software that goes through well defined
cycles of alpha/beta development towards a release, different parts of
ns are at different levels of maturity. For example, the TCP code is
quite mature, while the newest S-MAC code is still at an alpha stage.
Thus, the distinctions in the old numbering scheme were not useful.
We call the new release 2.26 because it's the 26th release in the ns-2
series. Our hope is that this version will be less confusing than the
alternatives, and a clear shift in the version numbering scheme.
Similarly, the current nam release is nam-1.9.
What's new in ns-2.26
* SMAC, a MAC protocol for wireless sensor networks added to ns. SMAC,
designed by WeiYe improves energy consumption by allowing periodic
sleep-wakeup cycles for nodes. Read mac/smac.cc for details on
functionalities supported in this first-cut version of smac.
* GEAR added to directed diffusion, to allow geographically limited diffusion.
* Simple web server model added to reflect server's processing delay for
web traffic. This model supports two scheduling policies:
first-come-first-serve and shortest-task-first.
* Extend web traffic model to support traffic generation according to
HTTP log files.
* QuickStart TCP was ported into ns. QuickStart is an experimental
proposal to allow end nodes to ask permission from routers for high
initial sending rates.
* Couple of new schedulers were added :
-STL based map scheduler from George Riley.
-Splay scheduler from Yuri Pryadkin.
A splay scheduler provides good average case-performance.
In practice, we found that the calendar scheduler remains faster,
however, and so the default scheduler has not been changed.
* LMS (light-weight multicast) module added to ns.
* JoBS, a new queuing discipline that provides quality-of-service (QoS) to
traffic aggregates contributed by Nicolas Christin was ported into ns.
Extensions and bug-fixes
* Mac-802.11 now allows random slot selection in the contention window
everytime a brdcast or an RTS pkt is sent out. Fix provided by Fred Stann.
* mac-802.3 now supports packet reference counting which results in memory
* Added support for fullTCP and variable packet size for RAMP.
* Event-tracing added to SRM and PGM.
* Several functonalities were added and bug fixes made to directed
diffusion module. The current diffusion module in ns corresponds to 3.1.3
version of the testbed implementation. See SCADDS page at
http://www.isi.edu/scadds/software for details on the latest directed
diffusion (testbed) release available.
* Improved animation for broadcast packets in nam. See below in "what's
new in nam-1.9" for details.
* The ns source code (including the emulation module) now builds on Darwin
(mac OS X).The ns source also builds for gcc-3 systems (like Redhat Linux
* A bug in DSR causing large TTL drops due to packets looping now fixed.
Also added a priority-queue for DSR that maintains separate queues for
different priority classes like routing, real-time, arp and normal packets.
* Several bug-fixes and improvements made to calendar and real-time
scheduler that enhances the scheduler speed and performance.
* Several bug-fixes and enhancements made to emulation code.
* Several bug-fixes were made to TCP and drop-tail/RED queue implementations.
What's new in nam-1.9
* Improved animation for broadcast packets in nam includes:
Broadcast packets used to be animated in real time, not virtual time. so
if you changed the playback speed (or even paused it) the circles would
always expand at the same real rate. Now, the animation is done in
virtual time, like all other objects. So if you slow down the playback
rate, the circles will move slower. If you increase playback rate, they
The animation speed for brdcast packets can now be set using:
v -t 0.0 -e set_bcast_duration 0.02
Previously a hardcoded value was used.
* Wireless and wired nodes can now be mixed with better results. This
requires using the "W" event as well as supplying X and Y coordinates for
all nodes in the scenario.
* wireless broadcast packets now use "r" events when animating in reverse,
just like non-broadcast packets. (previously they used the "h" event even
when going backwards).
* The range and duration of the animation of wireless packets can now be
specified on either a per-packet basis or by setting global parameters.