Cisco 6800 Series Administration Manual page 32

Network Protocols
Network Protocol
Internet Protocol (IP)
Link Layer Discovery Protocol
(LLDP)
Link Layer Discovery
Protocol-Media Endpoint Devices
(LLDP-MED)
Network Transport Protocol (NTP)
Real-Time Transport Protocol
(RTP)
Real-Time Control Protocol
(RTCP)
Cisco IP Phone 6800 Series Multiplatform Phones Administration Guide
18
Purpose
IP is a messaging protocol that
addresses and sends packets across
the network.
LLDP is a standardized network
discovery protocol (similar to CDP)
that is supported on some Cisco and
third-party devices.
LLDP-MED is an extension of the
LLDP standard developed for voice
products.
NTP is a networking protocol for
clock synchronization between
computer systems over
packet-switched, variable-latency
data networks.
RTP is a standard protocol for
transporting real-time data, such as
interactive voice and video, over
data networks.
RTCP works in conjunction with
RTP to provide QoS data (such as
jitter, latency, and round trip delay)
on RTP streams.
About the Cisco IP Phone
Usage Notes
To communicate with IP, network
devices must have an assigned IP
address, subnet, and gateway.
IP addresses, subnets, and gateways
identifications are automatically
assigned if you are using the Cisco
IP Phone with Dynamic Host
Configuration Protocol (DHCP). If
you are not using DHCP, you must
manually assign these properties to
each phone locally.
The Cisco IP Phone supports LLDP
on the PC port.
The Cisco IP Phone supports
LLDP-MED on the SW port to
communicate information such as:
• Voice VLAN configuration
• Device discovery
• Power management
• Inventory management
For more information about
LLDP-MED support, see the
LLDP-MED and Cisco Discovery
Protocol white paper at this URL:
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Cisco IP Phones have an NTP client
integrated into the software.
Cisco IP Phones use the RTP
protocol to send and receive
real-time voice traffic from other
phones and gateways.
RTCP is disabled by default.