Packet Loss Recovery Config

[ahenning]

Note: Eventually this forum post will be removed, since it is a duplicate of the Packet Loss Recovery.

Note: Packet Loss Recovery constitutes three features. Fast Retransmit Replay, Fast Retransmit Request, Forward Error Correction

From v.4 onward PLR is auto configured and FEC is optional.

With 2.0.2 packet loss recovery (PLR) has been made very dynamic to changing network conditions. This also provides Packet Order Correction.
This setting is optional. The default mode is used if the peer ip is not configured.

PLR and POC are simply enabled in the MultiSite tab by specifying the remote wanos IP:







Caveats:
In the first example the remote peer ip is in the same subnet as the site subnets and no further config is needed. In the second example, the remote peer ip is in a different subnet and it is added to the site to link the two.

Requirements:
Very specific traffic policies are required on each end for the remote site. Bypass any subnets not being optimized e.g. un-optimized remote sites and WAN devices. Wanos will automatically disable the feature per peer if it detects that packets cannot be recovered e.g. destined to the router. Hence its best to have specific source-destination policies.

The default gateway needs to be on the wan0 side, else false positive peer detected on lan0 messages could be logged.

Expected Log sequence:
rsp_peer0 - State set to CLOSED
rsp_peer0 - State set to SYN_SENT
rsp_peer0 - State set to SYN_RCVD
rsp_peer0 - State set to OPEN

[ahenning]

Difference in cold compression ratio with and without PLR enabled from empty datastores:
File Silesia Corpus Archive

Stats:

[itmildura]

Hi Antonie,
What does the second last line here mean.  WARNING - Maximum retransmits reached, changing mode to server.

Tue Mar 10 15:05:18 2015 : rsp_peer1 - State set to CLOSED
Tue Mar 10 15:05:18 2015 : rsp_peer1 - State set to SYN_SENT
Tue Mar 10 15:05:20 2015 : rsp_peer1 - State set to SYN_RCVD
Tue Mar 10 15:05:20 2015 : rsp_peer1 - State set to OPEN
Tue Mar 10 15:05:20 2015 : comp1 WComp Info - Clearing force stateless.
Tue Mar 10 15:05:50 2015 : rsp_peer0 RSP WARNING - Maximum retransmits reached, changing mode to server.
Tue Mar 10 15:05:50 2015 : hard setting force

[ahenning]

Generally it means the policies need to be more specific. In this case it could simply be that there is no peer for 'Site 0'. Site-1 looks ok.

It is a fail-safe mechanism to switch PLR on and off when it detects that PLR is not possible. It could for example also be logged when WAN link goes down.

'Warning' is perhaps the wrong word. We will change it to Info once the PLR status is visible in the gui.

[ahenning]

PLR is improving: http://youtu.be/SfSUgvngZjc

Test: Wanos Packet Loss Recovery and Packet Order Correction features.
Result: Packet Loss Recovery provides up to 10x TCP Acceleration under these lossy conditions:

Link details:
5% Packet Loss
50 ms latency
10 Mbps

Steps:
First test: Control test of a compressed file copy with all Wanos features disabled.
Second test: Compressed files are copied over the Wan link with only Packet Loss Recovery enabled.

Wan Optimizer 200.
Deduplication: Disabled
Compression: Disabled

[lexyus]

Dear ahenning,

if i have two sites with site A (192.168.6.0/24 and wanos ip is 192.168.6.41) and site B (192.168.7.0/24 and wanos ip is 192.168.7.41),
how to config multisite so that PLR will be enabled?

[ahenning]

On site A:





Site B would be a mirror config.

Note though with express PLR will automatically be disabled if the optimized throughput on Wan Tx is over 6 mbps