SD-WAN without FEC and packet duplication features can dynamically move traffic to the best VPN tunnel to ensure the best performance from the links available.
From my understanding packet duplication and FEC come into play and improve that end user experience further in the following 2 scenarios.
Scenario 1:
There are 2 WAN links available and voice traffic is passing over both links when Packet duplication is enabled. And only WAN 1 only when packet duplication is disabled. We then experience intermittent performance degradation/brownout or a complete failure of WAN 1
WITH FEC/PACKET DUPLICATION
FEC and packet duplication can offer a seamless transition over to WAN 2 resulting in no noticeable impact to the end user.
WITHOUT FEC/PACKET DUPLICATION
Without this technology the end user will experience a disruption to the service and will last the duration of time it takes for the vendor equipment to detect the loss and failover to the second WAN link. This time varies based on vendor but in my experience it’s typically sub second.
Scenario 2
There are 2 WAN links and both are experiencing intermittent performance degradation/brownout.
WITH FEC/PACKET DUPLICATION
Because traffic is being duplicated over both WAN links the packet has a better chance of arriving at the destination.
WITHOUT FEC/PACKET DUPLICATION
Because only 1 WAN link is being used the SD-WAN will pick the best of the bad links. Meaning the end users experience will suffer from all the loss, latency and jitter on that WAN link.
In my mind there is no question that FEC/ packet duplication is a innovation that improves the end user experience. This feature from my experience really resonates with customers and facilitates them buying into the SD-WAN technology.
Now, to the points I would like us to debate
With regards to scenario 1, a sub second disruption while the failover takes place is tolerable for the majority of businesses.
With regards to scenario 2, how frequently does this scenario come about? If the ISPs that you a using take a similar path over the internet then there is a very good chance the end user experience will be poor regardless. Secondly, if the customer is using ISPs that are using diverse paths over the internet then the likelihood of this scenario happening is drastically reduced.
I predominantly work with SME customers based in Europe and the USA where they are looking at dual broadband links with there SD-WAN solution.
Is the benefit of packet duplication and FEC often over valued? I work for a partner that offers two SD-WAN solutions, one that supports FEC and packet duplication, and one that doesn’t, with the price difference being approximately 3 times. In addition you are also increasing your bandwidth consumption, a resource which is typically a bottle neck for organizations.
If we put aside for the moment all other technical differences that the two vendors have, also the sales aspect which typically involves trying to take as much money as possible from the customer.
When would you pay 3 times the price to allow you to go with a vendor that offers FEC and packet duplication if that was the only relevant differentiator between the two vendors?
My belief is that it’s going to most likely be large global enterprises who often have branches in areas with poor connectivity options. Possibly with with a high dependence on real time traffic. Who probably know the cost to the business of any disruption to these services and are happy to absorb the higher cost to get this feature.
For a lot of my customers I feel that this technology is potentially overkill especially as they are operating in areas of the globe where connectivity options are generally good. I don’t feel the price difference is great value for money.
Apologies for the long winded rambling nature of this post. I suppose it’s more of a series of statements I would like you to approve/challenge and really just give your insight on as I’m still pretty fresh to this technology. It would be great to hear from people who have extensively tested both and understand why they chose one over the other based on this FEC/packet duplication
No comments:
Post a Comment