CRTP Configuration Command Directory
debug
ip rtp header-compression
ip rtp compression-connections
show
ip rtp header-compression
This chapter describes CRTP commands. CRTP is used on the low-speed serial linkage. The command
can be used for compressing the header of RTP packet to effectively lower the
occupation of bandwidth. At the same time, due to the reduction in packet length,
the delay of packet transit on the linkage can be shortened substantially.
debug ip rtp
header-compression
[no]
debug ip rtp header-compression
global
configuration mode
Router#debug ip rtp
header-compression
21:39:30: RHC Serial1/0: output
COMPRESSED_RTP, conn 0, cksum 0x0000, seq 30315, Gen = 0
Area |
Explanation |
21:39:31 |
Current
time of system |
RHC |
RTP header
compression |
Serial
1/0 |
Interface number |
Recv(output) |
Input or output |
COMPRESSED_RTP(uncompress) |
Packet type |
Conn |
Connection
number |
Cksum |
UDP
check sum |
Seq |
RTP
sequence number |
Gen |
Generation value of CRTP packet |
This command is needed to use under
interface configuration mode for activating CRTP on the serial linkage. The “no”
format of the command can be used for forbidding CRTP.
no ip rtp
header-compression
iphc-format |
Obeying CRT Pprotocol of rfc2507 IPHC
standard |
cisco-format |
the format of IPCP negotiation packet that use the cisco
format |
passive |
CRTP packet started to be transmitted after receiving
CRTP packet of the opposite terminal. |
default:
It is under forbidden state without configuring the
command. When this command is configured, the default is passive in the case of without adding optional
parameters.
interface
configuration mode
Currently CRTP is supported only on the
serial linkage of PPP encapsulation and will be extended to Frame Relay、HDLC and ISDN port, etc. The
command should be configured simultaneously on the two terminals of serial
linkage, otherwise it will not work. Meanwhile, when the relative header of
effective load of packet is relatively small, this protocol is quite
applicable. However, when the header is far below net load, it will reversely
add the processing spending of the router for the packet. Therefore, the
protocol is used for transmitting the similar RPT packet on the linkage.
Router_config#interface
serial 1/2
Router_config_s1/2#ip rtp
header-compression
Router_config_s1/2#ip rtp
compression-connections 25
Router_config_s1/2#enc ppp
Router_config_s1/2#
ip rtp
compression-connections number
no ip rtp
compression-connections
number The maximum linkages of local-reserved
CRTP
15 connections
interface
configuration mode
The number
of RTP dialogue that
is likely to occur simultaneously on the linkage can be estimated under general
condition. It will be tight when the number of the configured connection is
bigger than that of RTP dialogue.
Router_config#interface
serial 1/2
Router_config_s1/2#ip rtp
header-compression
Router_config_s1/2#ip rtp
compression-connections 25
Router_config_s1/2#enc ppp
Router_config_s1/2#
show ip rtp
header-compression [type number] [detail]
type number (optional)
Interface type and interface number, such as serial 1/0
detail (optional) showing detailed
information of each link
global
configuration mode
Router#sh ip rtp header-compression
RTP/UDP/IP header
compression statistics:
Interface Serial1/0:
0 dropped, 0 buffer copies, 0 buffer failures
336735 bytes saved, 197685 bytes sent
Connect: 15 rx slots, 15 tx
slots, 14 long searches, 1 misses
Router#
Keyword explanation of command
display is made in the form below
Keyword |
Explanation |
Interface
Serial1/0: |
Interface number and interface type |
Rcvd:
total |
Total
of CRTP packet received at the port. |
Compressed |
Total of compressed CRTP packet |
Errors |
Total of erroneous packet received. |
Dropped |
Total of directly deleted packet
received. |
buffer
copies, |
The
number of the packet that should be copied and saved. |
buffer
failures |
The number of failures of applying for
memory at the time of restoring normal IP packet. |
Sent:
total |
Total of CRTP packet sent. |
Compressed |
Total of compressed CRTP packet sent. |
bytes saved |
Saved bytes |
bytes sent |
Real byte sent |
Connect: rx slots |
Total of data structure received. |
tx slots |
Total of data structure sent |
long searches |
It is needed to search in transmit data
structure so as to determine the number of which to be used. |
Misses |
Search
the number of failure of data structure. |