Abstract: Measures for processing data in a packet-switched network. A first device is configured to snoop control packets of a predetermined control plane protocol in the network. The predetermined control plane protocol is operated by a plurality of other devices in the network to obtain Layer 2 information on the basis of known Layer 3 information. The first device does not operate the predetermined control plane protocol in the network. At the first device, in response to identifying that a given snooped packet was generated according to the predetermined control plane protocol. Layer 3 information associated with a second device in the plurality is extracted from the given snooped control plane protocol packet on the basis of known Layer 2 information associated with the second device. The second device is connected to the first device.

Abstract: Measures for processing data in a packet-switched network. At a first device in the network, a packet transmitted from a second device in the network is received. The received packet comprising an Internet Protocol (IP) address for a third device in the network. On the basis of the IP address for the third device comprised in the received data packet, lookup in an IP routing table of the second device is initiated to obtain a next-hop address for the received packet. The obtained next-hop IP address is determined to be an IP address of a device connected to the first device.

Abstract: Measures for processing data in a packet-switched network. At a first device in the network, an echo request packet is transmitted into the network. The echo request packet comprises a predetermined identifier. An echo response packet is received from a second device in the network. In response to the received echo response packet comprising the predetermined identifier, the received echo response packet is identified as a packet generated on the basis of an echo request packet originated from the first device, and an Internet Protocol (IP) address comprised in the received echo response packet is determined to be an IP address of the second device.

Abstract: Measures for processing data in a packet-switched network. A first device is configured to snoop control packets of a predetermined control plane protocol in the network. The predetermined control plane protocol is operated by a plurality of other devices in the network to obtain Layer 2 information on the basis of known Layer 3 information. The first device does not operate the predetermined control plane protocol in the network. At the first device, in response to identifying that a given snooped packet was generated according to the predetermined control plane protocol. Layer 3 information associated with a second device in the plurality is extracted from the given snooped control plane protocol packet on the basis of known Layer 2 information associated with the second device. The second device is connected to the first device.

Abstract: Measures for processing data in a packet-switched network. At a first device in the network, a packet transmitted from a second device in the network is received. The received packet comprising an Internet Protocol (IP) address for a third device in the network. On the basis of the IP address for the third device comprised in the received data packet, lookup in an IP routing table of the second device is initiated to obtain a next-hop address for the received packet. The obtained next-hop IP address is determined to be an IP address of a device connected to the first device.

Abstract: Measures for processing data in a packet-switched network. At a first device in the network, an echo request packet is transmitted into the network. The echo request packet comprises a predetermined identifier. An echo response packet is received from a second device in the network. In response to the received echo response packet comprising the predetermined identifier, the received echo response packet is identified as a packet generated on the basis of an echo request packet originated from the first device, and an Internet Protocol (IP) address comprised in the received echo response packet is determined to be an IP address of the second device.