The MPLS WG Archive[Date Prev][Date Next][Thread Prev][Thread Next] [Date Index][Thread Index][Author Index][Subject Index] MPLS Trafficdriven
Geoff It may be worth mentioning here that in MPLS we have the option to completely ignore the TOS bits in the IP packet and write our own COS into the EXP field of the MPLS shim header this can be done either by trusting the settings from the customer or by filtering on TCP/UDP port number to define the traffic type before assigning a class and writing the EXP MPLS traffic is prioritised through the network by the EXP field so if you neglect to configure a copy into or fresh write of the exp field I am not sure what the default behaviour is Can any one answer that question for me Hill -----Original Message----- From: mpls-ops-request@mplsrc.com [mailto:mpls-ops-request@mplsrc.com]On Behalf Of mpls-ops@mplsrc.com Sent: 26 April 2001 08:18 To: Geoff Bennett; Hass, Barry; Marinzulich, Matias; 'Ashwin Moranganti'; 'MP LS'; MPLS@UU.NET; mpls-ops@mplsrc.com Subject: RE: MPLS Trafficdriven geoff, As U mentioned..... "But the problem is how do you recognise the appropriate traffic types." Well we can solve this Problem: In the Ingress Router the ASIC device is already Configured to handle respective Packet types based on Profiles/Policies. End user can set the DSCP field in the transmitted IP packet to the Ingress Router. Now after receiving the IP Packet, Router checks the IP address and the DSCP field then validates via looking into the Port number and other stuff. By the way ASIC must be configured with such stuff to process such Traffic. Hence if somebody is sending email but prtending this is a VoIP packet it can be easily detected and either packet can be dropped or DSCP field changed accordingly. This is completely a configuration issue as to how to set up the ASIC for what type of traffic. SNMP or CLI can be used to configure such things. Hope, this helps........ vola --- Geoff Bennett <geoff.bennett@marconi.com> wrote: > Hi Barry, > Yes it would make sense. But who sets the DSCP field? > > The "end user" can't be allowed to do this because DSCP is used to > prioritise traffic, and everyone would set their traffic to high priority. > > The ideal thing would be to build proxy devices to insert the appropriate > value according to a policy. IMHO the obvious location for such a proxy is > the Ingress LSR. But the problem is how do you recognise the appropriate > traffic types. > > Cheers, > Geoff __________________________________________________ Do You Yahoo!? Yahoo! Auctions - buy the things you want at great prices http://auctions.yahoo.com/ ------- The MPLS-OPS Mailing List Subscribe/Unsubscribe: http://www.mplsrc.com/mplsops.shtml Archive: http://www.mplsrc.com/mpls-ops_archive.shtml |
|