topic Re: css persistence, flows, sticky, etc.... in Application Networking

css persistence, flows, sticky, etc....

d.alves — Mon, 20 Oct 2003 19:00:34 GMT

I am trying to understand the differences and similarities of persistence, flows and sticky. The documentation on this subject is not very helpful. Can someone out there provide a simple explanation of these three very important concepts?

Thanks in advance!!

Re: css persistence, flows, sticky, etc....

d.parks — Mon, 20 Oct 2003 19:14:25 GMT

Here's my interpretation:

Persistence: This setting determines whether or not the CSS will allow persistent HTTP connections. i.e. will a browser be allowed to maintain a single TCP connection for multiple requests, or will it be required to open an individual TCP connection for each bit of content. In web-server speak, this is sometimes referred to as "keepalive"

Flows: A flow is CSS speak for a TCP connection. Once a flow is established, an FTP connection for example, the CSS will maintain that flow for the duration of the connection. The CSS will not loadbalance traffic "mid-flow" except under unique circumstances, when a service goes down and remap is configured for example.

Sticky: The various sticky configurations come in to play when you want to have all connections from a particular client go to a particular service. This is most often accomplished with cookies, or sticky tables which track a clients' IP addresses. There is a limit to the size of the IP address table, so cookies scale better for web content.

Re: css persistence, flows, sticky, etc....

jfoerster — Tue, 21 Oct 2003 06:31:50 GMT

HI,

a bit more in detail regarding persistency.

In HTTP 1.1 there are multiple gets per HTTP-Session so if you use persistency all requests in the HTTP-Session will hit the same server. This denies the possibility to offload content (e.g. JPGs) to a cache. If you do not use persistency you split the HTTP1.1 session in multiple HTTP-Sessions on the CSS.

Hope that helps in regards of persistency.

Regards,

Joerg

Re: css persistence, flows, sticky, etc....

d.alves — Wed, 29 Oct 2003 14:48:38 GMT

Thanks for the reply. It was very helpful.

Re: css persistence, flows, sticky, etc....

d.alves — Wed, 29 Oct 2003 14:50:19 GMT

This was a big help to me regarding my understanding of persistency. Thanks!!

Re: css persistence, flows, sticky, etc....

jfoerster — Thu, 30 Oct 2003 06:05:16 GMT

HI Davon,

glad to hear that.

Please close this posting so that anyone sees that this issue has a "solution" and if you want to, feel free to rate the postings.

Kind Regards,

Joerg