The official System Requirements for Microsoft Dynamics GP 2018 document from Microsoft does not give Network requirements. So some companies may forget to ask or be tempted to think it doesn’t matter.
In fact, you must be aware that:
Dynamics GP is supported only when client and SQL databases are on the same Local Area Network (LAN).
Wide Area Networks (WAN), Virtual Private Networks (VPN), or any other variant is not supported and will cause at minimum poor performance, and at worst corrupted data.
A minimum of 1GBps LAN is required for normal GP performance. This also means that notebook users should be discouraged from using Wi-Fi to run Dynamics GP. CAT5 cabling is the minimum acceptable connection.
If you have a mix of speeds with LAN and WAN/VPN users, it gets even scarier. Dynamics GP tags each transaction with a Dex Row ID and that next number is reserved until the transaction is complete. If you have a local (fast connection) client and a remote (slow connection) client processing orders simultaneously, there is a possibility that these IDs could be assigned to the wrong transaction depending on whose transaction completes faster, which would corrupt the transaction. That is a very simplified layman’s description but should serve to show the importance.
As faster internet speeds become more cost-effective it gets more tempting to put space between client and servers or put the SQL server in a data center, but even if your network card says 1Gbps, it is not going to achieve that speed over a lossy WAN or VPN with a likely maximum of 50-200Mbps.
If you are implementing Microsoft Dynamics GP for the first time, make sure you review the system AND network requirements carefully.If you are already running Microsoft Dynamics GP and you are thinking of making a change to your network make sure you contact your Dynamics GP Partner to review your plans BEFORE making any changes.
Additional resources:
A short article on the problem of running database applications over WAN. Terminal Services is one solution when users and the database(s) reside in different locations. The Dynamics GP Web Client is another solution, but still requires a second collocated server for the underlying GP Client, IIS, and connection management database.
This article by Dave Musgrave is the best explanation on the subject of WAN ODBC communications.