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4. P frame
P frame is the one to compress and transfer encoded image of volumes of data by reducing the
time redundancy information of the encoded frame before the image sequence; it is called also the
predicated frame.
5. BBP frame
BBP frame is the video frame; it is mainly encoded as per the I
BBP BBP BBP… frame structure;
there are two B frame before each P frame.
6. Transparent channel
The transparent channel is a technology to send the analyzed IP data message to the serial ports,
acting to extend the control distance of serial equipment and use the IP network to control multiple
serial equipments. For users, it will only focus on point-to-point transfer, but not the network transfer
process; therefore it is called the serial transparent channel.
7
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DHCP
DHCP is the abbreviation of Dynamic Host Configuration Protocol; its former was BOOTP. BOOTP
was originally used for the network without disc host; the network host uses BOOT ROM to start and
connect with the network, but not the disc; whereas BOOTP can set TCP/IP environment for the host.
Actually it comprises two parts, i.e.: server terminal and client terminal. All IP network setting data are
controlled centrally by DHCP server, and the DHCP server is responsible for dealing with DHCP
requirement of client terminal; however, the client terminal will use the IP environmental data
configured by the server.
8. PPPOE
pppoe is the abbreviation of point-to-point protocol over Ethernet; it can make the host of the
Ethernet connect with a far-end access concentrator through a simple bridging device. Through the
pppoe protocol, the far-end access concentrator can realize the control and charging on each
accessed user. Comparing with the traditional connection mode, pppoe has the better cost
performance, and has been used widely in the network construction of residential community and other
application fields. Currently the popular bandwidth connection mode is ADSL, which is the one that
uses the pppoe protocol.
9.DDNS
DDNS is the abbreviation of Dynamic Domain Name Server. Based on DDNS, the dynamic IP
address of user will be mapped to a fixed domain name resolution service; every time when user
connects the network, the client-terminal program will transfer the dynamic IP address of the host to
the server program of the host of the service provider through the information transfer way; the service
provider program will provide the DNS service and realize dynamic domain name resolution. That is to
say, DDNS will capture the IP address that is changed by user, and then make it correspond to the
given domain name; if so the other online users will be available to make communication through the
domain name.
10.FTP
FTP is the abbreviation of File Transfer Protocol, used for making dual-way transfer on the control
file through Internet. Meanwhile, FTP is an application program, and user can connect its own PC with
all servers that use FTP protocol all over the world to access to the program and information on the
server.
The main function of FTP is to make a user connect with a remote computer (such computer must
use FTP server program) to view the files saved in the remote computer, and then copy such file to the
local computer, or send the file in the local computer to the remote computer.
11.UPNP
UPnP (Universal Plug and Play) is the general name of a set of protocols; it can not be deemed as
the UPnP=
“automatic port mapping. When downloading through Bitcomet, UpnP comprises two
aspects, i.e.:
1. For an Intranet computer, the UPnP function of BitComet can let the NAT module of gateway or
router make automatic port mapping, and map the port to be monitored by BitComet to the Intranet
computer through the gateway or router;
2. The network firewall module of gateway or router will open the port for the other computers on
the Internet.