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Application Level Routing in a Mesh Router?

Posted by Cliff on from the intelligent-packet-control dept.

faisaladeem asks: "Are there such mesh routers that can re-route the traffic based on QoS? (I'm not talking about traffic shaping) For example, if data rate of a video stream decreases due to an increase in congestion along the path then the router will re-route the stream dynamically to a different path to ensure the QoS for the video traffic. Since a mesh network has many paths or routes, it can be assumed that a less congestive path can be found if the existing path becomes bandwidth constrained. I heard that MPLS supports this kind of functionality? Secondly, can a router estimate the latency/bandwidth on a specific route ?"

1 of 23 comments (clear)

  1. To get your answer, first understand the question. by agristin · · Score: 5, Insightful

    Do you control the mesh of routers? Are they mesh routers (wireless type)? or are they many routers with connections to each other (deployed in a mesh)?

    I think you are asking the wrong question. You may need QoS for applications. You may need a mesh for high-availability or redundancy or efficiency. You probably don't need to conflate the two.

    QoS is to help in situations where bandwidth is used up. It drops, queues or buffers non-important traffic and forwards higher priority traffic first. If the network is solid, QoS is most helpful when bandwidth is used (or at least approaches capacity).

    Most routing protocols can incorporate bandwidth, delay and other network indicators: EIGRP does and OSPF can be configured to do so. You will need a routing protocol if you want to manage a "mesh of routers" without too much administrative pain.

    And now add policy based routing. You can combine a routing protocol with policy based routing to route high priority packets over a prefered network route, but if that route goes the protocol can route them another way.

    A routing protocol gives you redundancy and multiple paths (and the ability to take advantage of multiple paths). QoS avoids congestion, bandwidth and latency problems.

    _

    So if you have end to end QoS and routers with a capable routing protocol and maybe some policy based routing, your problem is fixed.

    But you asked about mesh routers (like firetide wireless?)... and wireless really doesn't have QoS standards- wireless QoS is kinda all proprietary now. So my best advice is:

    You should check with your sales engineer for your networking gear, if they can't answer- find a different vendor.

    I know several CCIE's who can answer this type of thing in their sleep.

    -A

    Oh and if you are asking this question and seriously positing MPLS as an answer, then you haven't done your homework. MPLS is not for wireless. MPLS is not something you implement or buy for your network- it is generally for carrier networks. Carriers can offer you some type of hand off and carry your traffic over an MPLS based network- but that won't fix your network, just traffic over the wan.

    If you posted more specific info, it would be easier to point you along in the right direction.

    And yes, this type of question is interesting to me, but this particular question is not conceived well in my opinion. And yeah, I do this stuff for fun and work.