Intelligent IP aggregate and DHCP client

Transcription

1 Intelligent IP aggregate and DHCP client Application Note AN123 Revision v1.4 August 2015

2 AN123 Intelligent IP aggregate and DHCP client 1 Overview 2 Notes This Application Note explains how you can set up an intelligent IP aggregate, where one unit is configured to use DHCP to obtain its IP address, and set up an IP tributary and enable it to route IP traffic to any destination. The IP aggregate allows you to use an IP connection as a normal Vocality aggregate link, to multiplex voice and data between two Vocality units. Previously it was necessary to fully configure both ends of the link with known IP addresses or DNS names, which led to additional work and created certain limitations traversing NAT gateways, when the real IP address of the remote unit would typically be hidden. When you define an IP aggregate a value 'ANY' can be configured in the 'peer address' field, in situations where the remote address is unknown or variable. In this case a password based authentication mechanism is used to ensure that only authorised multiplexors can connect. The remote site can be configured to automatically request its IP address from a DHCP server. This means that true plug and play operation is now possible, when installed behind a typical IP gateway using DHCP and NAT. This Application Note deals only with the additional steps necessary for configuration of an intelligent IP aggregate and DHCP client. If you have yet to configure IP aggregates, please refer to Application Note AN121 Configuring IP aggregates for detailed information. The value 'ANY' in the 'peer address' field can only be used at one end of the link, typically the hub. The Vocality unit at the other end of the link must be configured with the IP address of the hub, to which it should connect. The number of intelligent IP aggregates that need to be created will depend on how many remote nodes will be online and looking to communicate with this unit at any one time. When using DHCP to obtain an IP address you cannot set a default route to use a virtual channel e.g. 0:10 as it will be overwritten by the DHCP default route. 3 Hardware configuration The unit being configured is assumed to be connected via Ethernet cable to the associated LAN. 4 Software configuration 4.1 On the hub unit Configure a valid IP address in IP > Networks menu. If you are configuring an IP Trib, going from a public IP address on the hub to a private address on the LAN side of the remote, you will need to turn on NAT. You will need to set up a static route to the remote LAN. Create a new IP aggregate in the IP Aggregate menu and enter a description for the aggregate. Each aggregate must have a different name. In the 'PEER ADDRESS' field enter the value 'ANY', so that it does not matter which IP address is assigned to the remote unit from DHCP. Page 1 of 5

3 Specify the UDP port to use for this aggregate. (A unique UDP port must be set for every IP aggregate.) Specify the total bandwidth required for this aggregate, the rate at which you would like the aggregate to run. Select the Tx clock. Enter an authentication password, to permit remote connection to the hub - you will need to enter this twice, pressing <Return> each time. (Passwords must match at remote and hub). The following series of screenshots illustrates how this is done in practice: Figure 1 Hub unit with a public IP address configured Figure 2 Hub unit uplink configured as 'public' on NAT Figure 3 Hub unit IP trib configured as 'private' on NAT Your hub unit will need a default route for traffic to access the internet, as well as a route over the 0:10 tributary for traffic sent to the remote LAN. Page 2 of 5

4 Figure 4 Hub unit IP static route table 4.2 On the remote unit Figure 5 Hub unit IP Aggregates menu Configure the Ethernet port for DHCP in IP > Networks menu. Configure service management menus to route LAN traffic from the remote down 0:10 (Since DHCP assigns a default gateway routing all IP traffic out the port configured for DHCP, use of service management menus allows you to route traffic out to the internet without using a default gateway.) Create a new IP aggregate in the IP Aggregate menu and enter a description for the aggregate. In the 'PEER ADDRESS' field enter the IP address of the hub unit. Specify the UDP port for this aggregate to match the port set on the hub unit for this aggregate. Specify the total bandwidth required for this aggregate. Match the rate set here to the rate set on the hub unit for this aggregate. Select the TX clock. Enter the same authentication password used on the other unit - you will need to enter this twice, pressing <Return> each time. (Passwords must match at remote and hub). Again, the following series of screenshots illustrates how this is done in practice. On the IP > Networks menu set the uplink for DHCP, set the downlink for a private IP address to set up a LAN. Finally, set a tributary to the same address as downlink, mapped to 0:10 on the hub (Node 1). This will allow IP traffic from the remote LAN to access anywhere the hub unit has IP connectivity. Page 3 of 5

5 Figure 6 Remote unit configured for DHCP on the uplink port Figure 7 Remote unit configured to identify LAN traffic Figure 8 Remote unit configured to redirect LAN traffic to the 0:10 IP tributary Figure 9 Remote unit configured to redirect any traffic from to the 0:10 IP tributary Page 4 of 5

6 4.3 Confirming setup Figure 10 Remote unit IP Aggregates menu Finally, you can check that the DHCP client successfully received an IP address, and find out which address was assigned, by looking in the logs under Diagnostics >Logs > IP menu for a message of the form: 000d:00h:33m:13s:47 DHCP client: got address If the above configurations are set correctly, then you will be able to connect a laptop into the downlink port of the remote unit with an address of and a gateway of.1 and you should be able to access the internet, if the hub unit has access. (If the hub unit only has access to the corporate LAN, then the remote LAN on Node2 will have the same restriction.) 5 About Application Notes Application Notes are intended as a supplement to, rather than a substitute for, your User Manual. Should you have queries which are not answered by our current documentation, your local Vocality support team would be happy to hear from you. support@vocality.com. Page 5 of 5