I have a custommer complaining of problems with packet8 VOIP service. I was just wandering, we connect to the Internet at this location with 4 T1’s load balanced with Cisco CEF and per-packet load balancing. This supposeably results in out of order packets. Could this result in VOIP problems? I thought most VOIP devices used a jitter buffer to smooth things like this out.
We are upgrading to more T1’s and MLPPP in the next few months and I am just wandering if that will help?
Too bad Mikrotik does not support MLPPP. Save me from having to use a Cisco router.
You’d probably have the same problem with MT … any time you use load balancing and UDP you run into packets out of order… a small amount is okay, but very very touchy otherwise. Better to policy route - force VoIP down one pipe only, or at least keep it on the same pipe during that conversation.
“MLPPP, MLFR, and IMA typically use a round-robin algorithm to balance traffic among member links within a bundle, leading to fairly equal use of all links. However, it is now possible to receive (and forward) out-of-order packets. MLPPP compensates for this feature and buffers packets received out of order, and forwards packets only in order
(snip)
Is the bandwidth of member links T1 or less for MLPPP? (Links with greater bandwidth require more buffering and CPU resources, so Cisco recommends MLPPP on T1 or smaller links.) Is equal use of all links important? Are there delay-sensitive applications that do not do well with out-of-sequence packets (such as voice) on the network? If the answer to all three questions is “yes”, then MLPPP is necessary. The advantages of MLPPP are additional bandwidth, equal use of all links, and delivery of packets in sequence.”
According to Cisco, anyway. They have a tout about an upcoming product here that does a pretty good job of explaining MLPPP’s benefits if you don’t mind wading through all the Cisco dreck:
why dont you swtich to MT routers, use them to load balence, and then policy route those few customers who need voip to one pipe only… or just route their important traffic to that one pipe, and leave the rest load balenced…