Why to enable RFC-1323? What are the advantages of enabling RFC-1323?

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Article ID: 167620

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Updated On:

Products

Advanced Secure Gateway Software - ASG ProxySG Software - SGOS

Issue/Introduction

Why to enable RFC-1323? What are the advantages of enabling RFC-1323?

Resolution

RFC 1323 is a TCP enhancement for improving performance and reliability when transmitting data.

Before RFC-1323, the TCP window size was limited to 64K. This implied that without window scaling, TCP could only send 64k of data before waiting for an ACK. This RFC defines a new TCP option that allows a window size larger than 64K of data before window scaling.

Advantages of enable RFC-1323 support:

- Enhances the high-bandwidth and long-delay operation of the ProxySG appliances over very high-speed paths, ideal for satellite environments.

- Adds (besides window scaling) RTT calculations that helps with Retransmit TimeOuts (RTO).

- Allows selective ACK with better recovery for dropped packets and Protection Against Wrapped Sequence numbers (PAWS).

NOTE:  Some servers or routers don't or are not configured to support TCP extensions for high performance as stated in RFC-1323.  This may cause difficulties later on.  If you do encounter difficulties when RFC-1323 is enabled on your proxy, please see TECH242703 for some troubleshooting information.