Head end

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Head end may refer to:

1. A central control device required by some networks (e.g., LANs or MANs) to provide such centralized functions as remodulation, retiming, message accountability, contention control, diagnostic control, and access to a gateway.
2. A cable television headend, a master facility for receiving television signals for processing and distribution over a cable television system.
3. A central control device, within CATV systems, that provides centralized functions such as remodulation.^[1]

In a VPN, for example, a headend device is an IPsec gateway at the central site, which accepts traffic from spoke sites. The gateway usually decrypts the traffic, and checks if it is intended for the central site. If so, the gateway routes the traffic to its final destination in the central site. Otherwise, the gateway reencrypts the traffic using the shared key between it and the final destination (another spoke site), and sends it through the router.

[edit] Notes

1. ^ Federal Standard 1037C, Telecom Glossary 2000 [1]

[edit] See also

Cable television headend