Aastra Telecom Pro 160 User Manual

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How Does Network Addressing Work?
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41-001190-01 Rel. 1.1, Rev. 00 
AastraLink Pro 160 Administrator Guide
How Does Network Addressing Work?
The first time an AastraLink Pro 160 starts up, it attempts to use DHCP to obtain 
an IP address from a server on the network. 
If that fails, the AastraLink Pro 160 then uses ZeroConf to assign itself an IP 
address within the range 169.254/16 (excepting the first and last 256 addresses in 
this range, which are reserved). The AastraLink Pro 160 uses its MAC address as 
a basis, then selects a random IP Address within the valid range. The AastraLink 
Pro 160 sends out ARP requests to see if the IP Address is already assigned to 
another device on the network. If so, the AastraLink Pro 160 assigns itself another 
random IP Address until it finds a free address. 
Once the AastraLink Pro 160 is up and running, the administrator can use the Web 
UI to assign a static IP address to the device. The next time the AastraLink Pro 
160 starts up, it uses the static address you assigned. 
If the AastraLink Pro 160 device’s public IP Address changes, the device sends an 
email message to notify the administrator. 
How Does IP Phone Auto-Configuration Work?
When an Aastra IP phone starts up on your IP phone network, the phone uses 
multicast DNS to automatically discover the presence of an AastraLink Pro 160 
device on the LAN. Once the AastraLink is discovered, the phone then obtains its 
configuration file from the device. 
Note: 
Multicast DNS may not traverse between switched network segments (due to spanning tree 
non-convergence) or across subnet routers; therefore, it may be necessary to connect IP phones to 
the same Ethernet segment or IP Subnet as the AastraLink, before they can register to the 
AastraLink Pro.
If you are registering a new IP phone with the AastraLink, the IP Phone UI 
prompts you to specify the user’s first name, last name, and email address. The 
AastraLink Pro 160 then automatically assigns the next free extension to the IP 
phone. 
If there are multiple AastraLinks present on the LAN, then the Aastra IP phone UI 
displays the list of AastraLinks. You then select which AastraLink the phone 
should use to obtain its configuration file.