Thanks Reinhard. I had read the standard before floating the mail. Actually what I wanted to know was how one can determine from within br_initial_port_cost() method the actual speed of the network interface being enslaved to the bridge port(so that the interface can be assigned an appropriate cost). Some card drivers provide ioctl's for this (like aironet wireless 802.11b card). But I am not sure about others. It seems there is no standard way to do this. In that scenario it seems that one has to configure the path cost using brctl command.
Thanks & Regards, Anurag Agarwal -----Original Message----- From: Reinhard Schwillinsky [mailto:[EMAIL PROTECTED]] Sent: Monday, December 23, 2002 3:56 PM To: Anurag Aggarwal, Noida Cc: [EMAIL PROTECTED] Subject: Re: [bridge:] [Bridge] Bridge port initial cost See page 108f of http://standards.ieee.org/getieee802/download/802.1D-1998.pdf: It is recommended that default values of the Path Cost parameter for each Bridge Port be based on the val-ues shown in Table 8-5, the values being chosen according to the speed of the LAN segment to which each Port is attached. NOTE - The values shown in Table 8-5 apply to both full duplex and half duplex operation. The intent of the recom-mended values and ranges shown is to minimize the number of Bridges in which path costs need to be managed in order to exert control over the topology of the Bridged LAN. [...] If the value of Path Cost can be set by management, the Bridge shall have the capability to usethe full range of values in the parameter ranges specified in Table 8-5, with a granularity of 1. Table 8-5 Path Cost Parameter Values Parameter Link Speed Recommended value Recommended range Range Path Cost 4 Mb/s 250 100-1000 1-65535 Path Cost 10 Mb/s 100 50- 600 1-65535 Path Cost 16 Mb/s 62 40- 400 1-65535 Path Cost 100 Mb/s 19 10- 60 1-65535 Path Cost 1 Gb/s 4 3- 10 1-65535 Path Cost 10 Gb/s 2 1- 5 1-65535 rgs Reinhard Anurag Aggarwal, Noida wrote: > Hi All, > Has anybody worked on the br_initial_port_cost() interface and > updated it to > handle ethernet network interfaces with data rate other than 10Mbps. Also, I > want > to also update it so that it can set suitable initial port cost for a token > ring > and wireless interface. Can anyone help me out with this? > > Regards, > Anurag Agarwal > _______________________________________________ > Bridge mailing list > [EMAIL PROTECTED] > http://www.math.leidenuniv.nl/mailman/listinfo/bridge > _______________________________________________ Bridge mailing list [EMAIL PROTECTED] http://www.math.leidenuniv.nl/mailman/listinfo/bridge
