High Latency issue over WAN

We remote location in Asia is accessing our head office thru Citrix, the bandwidth is not a issue but the high latency difinitely is an issue - with 750-800 ms latency, entering a G/L journal becoming an impossible task. Has any one experience on this and how to get around this?

Our approach on this high latency issue are:
a. Having own Citrix box on the remote site; and
b. Setting up a local database server and OCM some of the tables to that server. Using data replication to keep in sync with Head office (using 3rd party replication tool - not JDE one as this release they're no longer support it --- not sure which 3rd replication tools will be using)

Anyone has experiences on this?


Release: 810
Tools Release: 8.96C1
Platofrm: As400 DB2/400

Hi,

I would start testing option #a, it's easier and
cheaper to test and maintain than #b.

I did some research on this not too long ago.

Adding a remote Citrix server would not necessarily improve performance and may in fact degrade performance. The latency issue will fall on your users when they go to do the GL entries as they traipse thru the grid on a domestic fat client. My sense is that the issue will not necessarily improve by moving the data to your remote location. Replicating data is a reasonable solution if you can rely on the replication process. If the replication is JDE replication, you are likely to run into more issues as this is not really supported anymore (data replication goes away in future releases).

Consider creating a new ICA configuration that tailored for these WAN users. The process is documented on the Citrix website and is known as a "second listener". The second ICA listener can be tweaked to accomodate the high latency.

This way your local (LAN) Citrix users can continue to use the full features of Citrix with a high-bandwidth, low-latency connection.

Any sort of latency is going to provide an issue - and realistically Citrix is the best solution in the way you are operating currently.

If you attempt to move data across your network connection (including placing the client locally), you will run into even more of a latency issue as SQL Statements or replication statements will wait for the latency across the WAN - there are plenty of whitepapers that I have written based on actual customer implementations with poor latency. You'd end up with hours and minutes of delay, not milliseconds, as the latency stacks up.

Alternatively, since you are running 8.10 - you could try and use the JAS server as a solution for this site. The JAS application will work probably a little better for you.

Alternatively for Citrix, you should also evaluate a couple of steps to attempt to increase the performance :

1. Reduce the colors to 16 colors on the Citrix client. Less colors dramatically reduce the amount of bandwidth and the number of packets needed to traverse the WAN. OneWorld is developed with 16 colors in mind - so you should not see a major difference.

2. Make sure you are using the latest Citrix ICA client - and the latest Citrix Presentation Server. Also try and not to map drives or printers to the session.

3. Try tuning the Speedscreen technology. Make sure that the clients have enough cache space locally for the session.

With those modifications, you will minimize the impact of latency - but you will never truly remove the latency. I have successfully connected a cellphone over a bad WAN connection - and the performance isn't impossible to utilize - but even green screen will have an issue over a poor WAN configuration.

So in summary, either tune your Citrix client (which is the best and quickest method) or implement a JAS server and see what impact the JAS server has over poor latency.

Hope those steps help.

Another, additional, approach may be to look at the possibility of improving the link itself. Having suffered high latency (and high packet loss) on Internet links from the UK to China, we put in an MPLS link. This brought latency down from an erratic 900ms to a consistent 300ms and effectively removed the packet loss problem. However, it wasn't cheap..

Thanks your for all of your reply on this.... I will take all of your advises and move on. It is great that you're all willing to share.. I hope I will return something back later.

Cheers,