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eCM's ip address

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ramks
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Joined: 2010-06-17
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How can one get embedded Cable Modem's ip address?
I iterated through the available java.net.NetworkInterfaces. (NetworkInterface.getNetworkInterfaces)
There were two.
1. LocalHost - 127.0.0.1
2. eth0 - IP address of the PC.
I was expecting 2 NetworkInterfaces, one representing the eSTB and one representing the eCM.

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greg80303
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Joined: 2008-07-03
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Please refer to Annex B.2.3.1 of the OCAP 1.1.3 specification. An OCAP-J application can only determine the cable network return chanel IP address via the java.net.InetAddress.getLocalHost() method. Don't confuse this with ethernet ports (or other network interfaces) that may allow a set-top to communicate with a LAN in the home. Since your PC does not have a true cable network connection, I believe that we always just return the first discovered network interface IP as the return channel IP.
G

ramks
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Joined: 2010-06-17
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DHCP server in headend would allocate two IPs per box. isn't it?
One for the Host (I mean the entity which is different from MCARD and eCM) and one for eCM.
I assume return channel IP address is same as the one allocated for the Host.
So, there is no way for an OCAP app to get eCM IP address?

greg80303
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Joined: 2008-07-03
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The only way I can think of that might get you the eCM IP address is through SNMP (org.ocap.diagnostics). Let me check with some of my colleagues to see if an app can access eCM MIBs through this interface.
G

ramks
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Joined: 2010-06-17
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It is not hinted in MIBManager.queryMibs that OCAP app can query eCM MIBs. Is the API intended to access eCM MIBs also?

greg80303
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Joined: 2008-07-03
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We did some looking into this. It looks like there is no access to the eCM IP address through SNMP. The OpenCable Host Device 2.1 Core Functional Requirements (Section 14.7) provides access to a few eCM MIBs, but the IP address is not one of them.
G