Ask the Experts

[joshtseng]

Out-of-sequence packets within a TCP session can cause performance issues in a high-latency environment.  The Steelheads may have to retransmit the out-of-order packets, and this can be noticable if the packets are consistently being delivered out of order.

You can check reports-->networking-->tcp statistics.  If there is a particularly large number of TCP retransmits, then that's where I would look.

Josh

[gabedimeglio]

How is the Steelhead effected under the following circumstances?

This is the physical layout

Layer 2 LAN - Steelhead with HSRP - Encryption Devices - MPLS Routers - Cloud - MPLS Routers - Encryption Devices - Steelhead with HSRP - Layer 2 LAN

Scenario.

We are trying to encrypt and decrypt as you can see, but this causes NTP issues and some intermittent performance issues. I'm curious if it's possible that packets are arriving to the other Steelhead out of sequence and what impact this would have on the Steelheads ability to process the traffic.

Currently we have clear policies on the encryptors for NTP and various other traffic including Multicast.

If packet sequence is not an issue, then what protocols and ports could possibly cause such issues.

We are using simplified routing.

Thanks!