Planning Server Capacity

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

Table 10.11 provides capacity planning information that you can use to help determine how many demand-dial servers you need to deploy and how much data throughput your site-to-site connection can support.

Table 10.11   Capacity Planning

Factor Capacity

Number of connections

For two-way connections, one answering router supports 10 simultaneous calling router connections before performance begins to degrade.

  • For one-way connections, one answering router supports 100 simultaneous calling router connections before performance begins to degrade.

Data throughput

The amount of data throughput that a site-to-site connection can support depends, in part, on what resources the users are using on the network. Other factors that affect data throughput include:

  • IPSec offload card. You can increase data throughput for L2TP/IPSec by installing an IPSec offload card. Using an IPSec offload card and a dual processor lets a server process more than 50 Mbps of fully encrypted data. To install an IPSec offload card, follow the manufacturer’s instructions.

  • Compression. Using Microsoft Point-to-Point Compression (MPPC) decreases data throughput. To increase data throughput, turn off MPPC. You can turn off MPPC by using one of the following methods:

    • To clear compression on a specific demand-dial interface. In Routing and Remote Access, in the console tree, click Network Interfaces, right-click the demand-dial interface on which you want to clear compression, and then click Properties. On the demand-dial interface Properties page, click the Networking tab, click Settings, and then in the PPP Settings dialog box, clear the check box Enable software compression.

    • To clear compression for all types of PPP connections. In Routing and Remote Access, in the console tree, right- click the demand-dial server icon, click Properties, click the PPP tab, and then clear the check box Software compression. This disables compression both for site-to-site connections and for remote access connections.