MPLS RSVP TE - Priority setup / hold values
MPLS RSVP TE - Priority setup / hold values
Hi, I am really trying to get my head around how LSP's are pre-empted. I understand the values of 0 and 7 (highest priority and lowest priority so that LSPs will always be pre-empted or stay as they are) however I don't understand any of the other values in between 2-6. How do they relate to the importance of an LSP or LSP's? Is it if you have a number of LSPs contending so they can be rated for importance? Also, do the priority values relate to any specific bandwidth level? If anyone can explain in simple plain English (idiots guide!) that would be appreciated.
Re: MPLS RSVP TE - Priority setup / hold values
You can certainly think of the priority as the "importance" of an LSP.
What you are defining is what happens if there are multiple LSPs competing for the same resource such as a link. For example you might have an LSP for delay/jitter sensitive voice traffic that is more important than a data LSP. The VOIP tunnel would be able to push a lower priority LSP off a link where there is not enough bandwidth for both and make it recalculate a different path.
How you choose to proritise your LSPs is up to you - you have 8 values to play with. For the VOIP traffic example, perhaps it has a stringent SLA and generates high revenue whereas another LSP used for data backups is the opposite. The bandwidth used by a service might play a part in your decision to set a particuar priority - the voice traffic might be low bandwidth (but important) and the data backups LSP high bandwidth.
What you are defining is what happens if there are multiple LSPs competing for the same resource such as a link. For example you might have an LSP for delay/jitter sensitive voice traffic that is more important than a data LSP. The VOIP tunnel would be able to push a lower priority LSP off a link where there is not enough bandwidth for both and make it recalculate a different path.
How you choose to proritise your LSPs is up to you - you have 8 values to play with. For the VOIP traffic example, perhaps it has a stringent SLA and generates high revenue whereas another LSP used for data backups is the opposite. The bandwidth used by a service might play a part in your decision to set a particuar priority - the voice traffic might be low bandwidth (but important) and the data backups LSP high bandwidth.
