Wireless Mesh Networking - Revision history

Kingdavid: /* Network performance tools */

2007-02-22T21:15:05Z

Network performance tools

← Older revision		Revision as of 23:15, 22 February 2007
Line 204:		Line 204:
	Iperf		Iperf

	[http://dast.nlanr.net/Projects/Iperf/ main page]		* [http://dast.nlanr.net/Projects/Iperf/ main page]
	[http://onl.arl.wustl.edu/Tutorial/Filters,_Queues_and_Bandwidth/Generating_Traffic_With_Iperf.html How to]		* [http://onl.arl.wustl.edu/Tutorial/Filters,_Queues_and_Bandwidth/Generating_Traffic_With_Iperf.html How to]
	[http://dast.nlanr.net/Projects/Iperf/iperf_faq.php FAQ]		* [http://dast.nlanr.net/Projects/Iperf/iperf_faq.php FAQ]

Kingdavid at 21:14, 22 February 2007

2007-02-22T21:14:44Z

← Older revision		Revision as of 23:14, 22 February 2007
Line 194:		Line 194:

	'''See [[Links]] for other Mesh Network initiatives'''		'''See [[Links]] for other Mesh Network initiatives'''


			=Network performance tools=



			Summary of all network performance tools [http://sd.wareonearth.com/~phil/net/ttcp/ here]

			Iperf

			[http://dast.nlanr.net/Projects/Iperf/ main page]
			[http://onl.arl.wustl.edu/Tutorial/Filters,_Queues_and_Bandwidth/Generating_Traffic_With_Iperf.html How to]
			[http://dast.nlanr.net/Projects/Iperf/iperf_faq.php FAQ]

Kingdavid: /* Network Simulation */

2006-08-15T22:12:43Z

Network Simulation

← Older revision		Revision as of 00:12, 16 August 2006
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	Now fix your path environment by putting the following in .bash_profile		Now fix your path environment by putting the following in .bash_profile

	export PATH=$PATH:home/djohnson/ns-allinone-2.29/bin:/home/djohnson/ns-allinone-2.29/tcl8.4.11/unix:/home/djohnson/ns-allinone-2.29/tk8.4.11/unix		export PATH=$PATH:home/djohnson/ns-allinone-2.29/bin:/home/djohnson/ns-allinone-2.29/tcl8.4.11/unix:/home/djohnson/ns-allinone-2.29/tk8.4.11/unix
	export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/djohnson/ns-allinone-2.29/otcl-1.11:/home/djohnson/ns-allinone-2.29/lib		export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/djohnson/ns-allinone-2.29/otcl-1.11:/home/djohnson/ns-allinone-2.29/lib
	export TCL_LIBRARY=$TCL_LIBRARY:/home/djohnson/ns-allinone-2.29/tcl8.4.11/library		export TCL_LIBRARY=$TCL_LIBRARY:/home/djohnson/ns-allinone-2.29/tcl8.4.11/library

	Test the ns2 suite by running ./validate from the ns2 directory		Test the ns2 suite by running ./validate from the ns2 directory

Kingdavid: /* Network Simulation */

2006-08-15T22:06:02Z

Network Simulation

← Older revision		Revision as of 00:06, 16 August 2006
Line 94:		Line 94:

	At this stage, Opnet, Ptolemy, SimJava and OMNet++ appear to be most interesting...		At this stage, Opnet, Ptolemy, SimJava and OMNet++ appear to be most interesting...


			During 2006 it was decided to focus on the open source simulators, Omnet++ and NS-2

			'''Omnet++'''

			Download from [http://www.omnetpp.org omnetpp comunity site]
			After untarring the file make sure you put the following in your .bash_profile file
			export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:"/home/djohnson/simulators/omnetpp-3.1/lib"
			export PATH=$PATH:/home/djohnson/simulators/omnetpp/bin:/home/djohnson/simulators/omnetpp-3.1/bin"

			'''NS-2'''

			Download from [http://sourceforge.net/projects/nsnam ns2 sourceforge site>
			After untarring the file the following bug needs to be fixed

			If you find this error in your installation of the new version ns-allinone 2.29 2 :

			"checking system version (for dynamic loading)... ./configure: line 7624: syntax error near unexpected token ')'
			./configure: line 7624: ' OSF*)' tcl8.3.2 configuration failed! Exiting ...
			Tcl is not part of the ns project. Please see www.Scriptics.com to see if they have a fix for your problem."

			the problem is due to these files :

			# tcl: file tcl8.x.x/unix/tcl.m4.
			# tk: file tk8.x.x/unix/tcl.m4.
			# otcl: file otcl-1.x/configure.in.

			The line generating the problem is :

			system=MP-RAS-`awk ' { print $3 } '/etc/.relid'`

			The problem lies in how bash 3.1.x and 4.x.x parse the configure file. This will simply pass through bash 3.0.x and lower versions. So in order to make things work changed the above line to:

			system=MP-RAS-`awk ' { print $3 } '/etc/.relid`

			You will have to take following steps in order to bring the changes into effect: Remove the second last character ( ' ) from the line and do this for all the three files above. Now after changing the configuration files you will have to delete older configure file and any cache if it exists in the respective folders. After that do not forget to run autoconf from command line in the respective folders to generate a fresh configure file.

			And finally re-install it by the following command :

			./install

			Now fix your path environment by putting the following in .bash_profile

			export PATH=$PATH:home/djohnson/ns-allinone-2.29/bin:/home/djohnson/ns-allinone-2.29/tcl8.4.11/unix:/home/djohnson/ns-allinone-2.29/tk8.4.11/unix
			export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/djohnson/ns-allinone-2.29/otcl-1.11:/home/djohnson/ns-allinone-2.29/lib
			export TCL_LIBRARY=$TCL_LIBRARY:/home/djohnson/ns-allinone-2.29/tcl8.4.11/library

			Test the ns2 suite by running ./validate from the ns2 directory

	=[[Voice over Mesh]]=		=[[Voice over Mesh]]=

Kingdavid: /* Mesh Partitioning problem due to BSSID issue */

2006-07-27T20:18:43Z

Mesh Partitioning problem due to BSSID issue

← Older revision		Revision as of 22:18, 27 July 2006
Line 64:		Line 64:
	One of the frustrating problems in 802.11 ad hoc networks is the issue of mesh partitioning due to the method 802.11 uses to form an ad-hoc network using the BSSID.		One of the frustrating problems in 802.11 ad hoc networks is the issue of mesh partitioning due to the method 802.11 uses to form an ad-hoc network using the BSSID.

	When 802.11 interfaces are put into Ad ~~Ho c mo de~~, they go through a somewhat complicated procedure to join what is known as a Basic Service Set, or BSS. A BSS is a kind of virtual network; even if two diﬀerent nodes are operating on the same channel, they will not “see” each other’s packets unless they are in the same BSS. Basic Service Sets are identiﬁed by a 6-byte number known as the Basic Service Set ID, or BSSID, which is transmitted in the header of every 802.11 frame. When an 802.11b adapter enters Ad Hoc mode, it is conﬁgured with a Service Set ID (SSID), which is a string that is intended to identify the network it wishes to join. The adapter then scans through all of the 802.11b channels, listening for beacons sent by other nodes. Beacons contain, among other things, the SSID and BSSID being used by the sending node. If the adapter hears a beacon containing the SSID that matches its own, then it joins this existing Basic Service Set by setting its own BSSID to the one received in the beacon.		When 802.11 interfaces are put into Ad Hoc mode, they go through a somewhat complicated procedure to join what is known as a Basic Service Set, or BSS. A BSS is a kind of virtual network; even if two diﬀerent nodes are operating on the same channel, they will not “see” each other’s packets unless they are in the same BSS. Basic Service Sets are identiﬁed by a 6-byte number known as the Basic Service Set ID, or BSSID, which is transmitted in the header of every 802.11 frame. When an 802.11b adapter enters Ad Hoc mode, it is conﬁgured with a Service Set ID (SSID), which is a string that is intended to identify the network it wishes to join. The adapter then scans through all of the 802.11b channels, listening for beacons sent by other nodes. Beacons contain, among other things, the SSID and BSSID being used by the sending node. If the adapter hears a beacon containing the SSID that matches its own, then it joins this existing Basic Service Set by setting its own BSSID to the one received in the beacon.

	If the adapter does not receive any beacons with a matching SSID within a certain period of time, it decides that no Basic Service Set currently exists with its SSID. In this case, it sets up itself as a new Basic Service Set by selecting a random BSSID and using that for all of its traﬃc. Any other nodes using the same SSID which start up in range of this node will hear its beacons and conﬁgure themselves to use its BSSID. This creates a serious problem for an Ad Hoc network. Namely, if two nodes start up at different times and are not within radio range of each other, they will start with different BSSIDs and be on different logical networks, despite both having the same SSID. Because 802.11 adapters ignore all frames whose BSSID does not match their own, this creates a partition in the network and prevents all of the nodes from being able to communicate prop erly.		If the adapter does not receive any beacons with a matching SSID within a certain period of time, it decides that no Basic Service Set currently exists with its SSID. In this case, it sets up itself as a new Basic Service Set by selecting a random BSSID and using that for all of its traﬃc. Any other nodes using the same SSID which start up in range of this node will hear its beacons and conﬁgure themselves to use its BSSID. This creates a serious problem for an Ad Hoc network. Namely, if two nodes start up at different times and are not within radio range of each other, they will start with different BSSIDs and be on different logical networks, despite both having the same SSID. Because 802.11 adapters ignore all frames whose BSSID does not match their own, this creates a partition in the network and prevents all of the nodes from being able to communicate prop erly.

	To solve this problem many new 802.11 devices allow you to manually set the BSSID to a specific 6 byte number of your chosing. If you set all the nodes in the mesh to this same BSSID you will avoid this problem.		To solve this problem many new 802.11 devices allow you to manually set the BSSID to a specific 6 byte number of your chosing. If you set all the nodes in the mesh to this same BSSID you will avoid this problem.


	=Network Simulation=		=Network Simulation=

Kingdavid at 20:14, 27 July 2006

2006-07-27T20:14:12Z

← Older revision		Revision as of 22:14, 27 July 2006
Line 59:		Line 59:

	More: [[IP Allocation]]		More: [[IP Allocation]]

			=Mesh Partitioning problem due to BSSID issue=

			One of the frustrating problems in 802.11 ad hoc networks is the issue of mesh partitioning due to the method 802.11 uses to form an ad-hoc network using the BSSID.

			When 802.11 interfaces are put into Ad Ho c mo de, they go through a somewhat complicated procedure to join what is known as a Basic Service Set, or BSS. A BSS is a kind of virtual network; even if two diﬀerent nodes are operating on the same channel, they will not “see” each other’s packets unless they are in the same BSS. Basic Service Sets are identiﬁed by a 6-byte number known as the Basic Service Set ID, or BSSID, which is transmitted in the header of every 802.11 frame. When an 802.11b adapter enters Ad Hoc mode, it is conﬁgured with a Service Set ID (SSID), which is a string that is intended to identify the network it wishes to join. The adapter then scans through all of the 802.11b channels, listening for beacons sent by other nodes. Beacons contain, among other things, the SSID and BSSID being used by the sending node. If the adapter hears a beacon containing the SSID that matches its own, then it joins this existing Basic Service Set by setting its own BSSID to the one received in the beacon.

			If the adapter does not receive any beacons with a matching SSID within a certain period of time, it decides that no Basic Service Set currently exists with its SSID. In this case, it sets up itself as a new Basic Service Set by selecting a random BSSID and using that for all of its traﬃc. Any other nodes using the same SSID which start up in range of this node will hear its beacons and conﬁgure themselves to use its BSSID. This creates a serious problem for an Ad Hoc network. Namely, if two nodes start up at different times and are not within radio range of each other, they will start with different BSSIDs and be on different logical networks, despite both having the same SSID. Because 802.11 adapters ignore all frames whose BSSID does not match their own, this creates a partition in the network and prevents all of the nodes from being able to communicate prop erly.

			To solve this problem many new 802.11 devices allow you to manually set the BSSID to a specific 6 byte number of your chosing. If you set all the nodes in the mesh to this same BSSID you will avoid this problem.


	=Network Simulation=		=Network Simulation=

Yusufk: /* Voice over Mesh */

2006-01-19T09:52:24Z

Voice over Mesh

← Older revision		Revision as of 11:52, 19 January 2006
Line 86:		Line 86:

	=[[Voice over Mesh]]=		=[[Voice over Mesh]]=
	The aim of this topic of research will be to conduct a [[Protocol QoS Shoot-out]] in order to determine the optimum protocols and configuration required to provide the QoS needed for voice communiction ([[VOIP]]) over a mesh network.		The aim of this topic of research will be to conduct a [[Protocol QoS Shoot-out]] in order to determine the optimum protocols and configuration required to provide the QoS needed for voice communiction ([[VOIP]]) over a mesh network. The experiments will be conducted on the [[49-node Indoor Mesh]], [[Pretoria Mesh]] and possibly the [[Mpumulanga Mesh]].

	=MAC Layer=		=MAC Layer=

Yusufk: /* Voice over Mesh */

2006-01-19T09:51:08Z

Voice over Mesh

← Older revision		Revision as of 11:51, 19 January 2006
Line 86:		Line 86:

	=[[Voice over Mesh]]=		=[[Voice over Mesh]]=
	The aim of this topic of research will be to conduct a [[Protocol QoS Shoot-out]]in order to determine the optimum protocols and configuration required to provide the QoS needed for voice communiction ([[VOIP]]) over a mesh network.		The aim of this topic of research will be to conduct a [[Protocol QoS Shoot-out]] in order to determine the optimum protocols and configuration required to provide the QoS needed for voice communiction ([[VOIP]]) over a mesh network.

	=MAC Layer=		=MAC Layer=

Yusufk: /* Voice over Mesh */

2006-01-19T09:50:50Z

Voice over Mesh

← Older revision		Revision as of 11:50, 19 January 2006
Line 86:		Line 86:

	=[[Voice over Mesh]]=		=[[Voice over Mesh]]=
	The aim of this topic of research will be to determine the optimum protocols and configuration required to provide the QoS needed for voice communiction ([[VOIP]]) over a mesh network.		The aim of this topic of research will be to conduct a [[Protocol QoS Shoot-out]]in order to determine the optimum protocols and configuration required to provide the QoS needed for voice communiction ([[VOIP]]) over a mesh network.

	=MAC Layer=		=MAC Layer=

Yusufk: /* [Voice over Mesh] */

2006-01-12T10:03:15Z

[Voice over Mesh]

← Older revision		Revision as of 12:03, 12 January 2006
Line 85:		Line 85:
	At this stage, Opnet, Ptolemy, SimJava and OMNet++ appear to be most interesting...		At this stage, Opnet, Ptolemy, SimJava and OMNet++ appear to be most interesting...

	=[Voice over Mesh]=		=[[Voice over Mesh]]=
			The aim of this topic of research will be to determine the optimum protocols and configuration required to provide the QoS needed for voice communiction ([[VOIP]]) over a mesh network.

	=MAC Layer=		=MAC Layer=