# Platform Considerations

For information about modules that support IP tunnels on the ERX7xx models, ERX14xx models, and the ERX310 Broadband Services Router:

- See ERX Module Guide, Table 1, Module Combinations for detailed module specifications.
- See ERX Module Guide, Appendix A, Module Protocol Support for information about the modules that support IP tunnels.

For information about modules that support IP tunnels on the E120 and E320 Broadband Services Routers:

- See E120 and E320 Module Guide, Table 1, Modules and IOAs for detailed module specifications.
- See E120 and E320 Module Guide, Appendix A, IOA Protocol Support for information about the modules that support IP tunnels.

## Module Requirements

The supported modules for creating IP tunnels depends on the type of E Series router that you have.

### ERX7xx Models, ERX14xx Models, and the ERX310 Router

To create dynamic IP tunnels on an ERX7xx model, ERX14xx model, or an ERX310 router, you must install a Service line module (SM) or a module that supports the use of shared tunnel-server ports. For information about installing modules in the ERX routers, see the ERX Hardware Guide.

SMs provide dedicated tunnel-server ports that are always configured on the module. Unlike other line modules, SMs do not pair with corresponding I/O modules that contain ingress and egress ports. Instead, they receive data from and transmit data to other line modules with access to ingress and egress ports on their own associated I/O modules. However, you must assign interfaces on other line modules or loopback interfaces to act as source endpoints for the tunnel.

You can also create IP tunnels on router modules that support shared tunnel-server ports. You can configure (provision) a shared tunnel-server port to use a portion of the module's bandwidth to provide tunnel services. For a list of the modules that support shared tunnel-server ports, see the ERX Module Guide.

To configure IPSec transport mode in the GRE or DVMRP destination profile, you must install an IPSec Service Module (ISM).

For information about configuring tunnel services on dedicated and shared tunnel-server ports, see Managing Tunnel Service and IPSec Service Interfaces in JunosE Physical Layer Configuration Guide.

All line modules forward traffic to IP tunnels. For information about which line modules accept traffic for IP tunnels, see the ERX Module Guide.

### E120 Router and E320 Router

To create dynamic IP tunnels on an E120 router or an E320 router, you must install an ES2 4G line module or an ES2 10G ADV line module (LM) with an ES2-S1 Service I/O adapter (IOA), or an IOA that supports the use of shared tunnel-server ports. For information about installing modules in these routers, see the E120 and E320 Hardware Guide.

The combination of an ES2 4G LM or an ES2 10G ADV LM with an ES2-S1 Service IOA provides a dedicated tunnel-server port that is always configured on the IOA. Unlike SMs, the ES2 4G LM and the ES2 10G ADV LM require the ES2-S1 Service IOA to condition it to receive and transmit data to other line modules. The ES2-S1 Service IOA also does not have ingress or egress ports.

You can also create IP tunnels on IOAs that support shared tunnel-server ports. You can configure (provision) a shared tunnel-server port to use a portion of the bandwidth of the IOA to provide tunnel services. For a list of the IOAs that support shared tunnel-server ports, see the E120 and E320 Module Guide.

All line modules forward traffic to tunnels. For information about the IOAs that accept traffic for tunnels, see the E120 and E320 Module Guide.

## Redundancy and Tunnel Distribution

For information about the redundancy and tunnel distribution mechanisms supported for SMs, the ES2-S1 Service IOA, and shared tunnel-server ports, see Configuring Dynamic IP Tunnels .