Design Options for DHCP on Routed Networks
Updated: November 10, 2008
Applies To: Windows Server 2008
Large enterprise networks typically consist of many subnets that use routers to segment and manage traffic. The BOOTP and DHCP address allocation protocols use broadcast traffic, which means you must pay careful attention to network planning to provide dynamic address allocation across the enterprise network.
You can configure DHCP on routed networks in the following ways:
Design Option 1: Multiple DHCP Servers
Design Option 2: BOOTP/DHCP Forwarding on Routers
Design Option 3: BOOTP/DHCP Relay Agents
Design Option 4: Multihomed DHCP Servers
The following are approaches you can take to ensure that DHCP servers can service clients across a routed network:
- Deployment of multiple DHCP servers, with at least one per subnet.
- Use and configuration of DHCP-compatible routers.
- Use and configuration of software-based relay agents.
- Deployment of multihomed DHCP servers.
For most scenarios, the best option is to use routers that support BOOTP/DHCP forwarding and are configured with addresses of DHCP servers as their helper address. Such a design requires fewer servers (even on large segmented networks) and minimizes DHCP broadcast traffic.