Operating Manual
KE3500
xDSL
M
ULTI
T
EST
Point-to-Point Protocol
The Point-to-Point Protocol (PPP) is, in information technology, a network protocol for initiating a connection
via switched lines. The protocol is based on HDLC and is the successor to SLIP as well as a series of
proprietary protocols of this type. The PPP over Ethernet protocol (PPPoE) regulates the encapsulation of PPP
packets inside Ethernet frames. PPPoE is used, for example, by Deutsche Telekom for Telekom DSL
connections (and for Telekom Bitstream, T-DSL-Resale connections and T-DSL Business Symmetrisch based
on SDSL); several (up to 10) PPPoE sessions to different Internet service providers can exist at the same time
using these Telekom DSL connections (exception: VDSL-based services including ADSL2plus paths
implemented by way of these DSLAMs) if these sessions can be terminated on DTAG-BBRASs (via OC, Gate
or Z-ISP). PPP over ATMPPPATMPPP over ATM protocol (PPPoA) regulates the encapsulation of PPP
packets inside ATM cells.
PTM
Data transmission method that divides the data into specific memory blocks that all possess information about
their respective destinations. It allows the long-distance data transmission lines of several devices to be
simultaneously used for data transmission. The packets are sent and relayed in a zipper method by the
different transmitters.
QLN
Quiet line noise describes noise in the line audible primarily when no other noise is being transmitted.
Router
Routers are network devices that can route network packets between several computer networks. They are
used most frequently for connection to the Internet, for the secure connection of several locations (Virtual
Private Network) or for the direct connection of several local network segments with adaptation to different
network protocols if necessary (Ethernet, DSL, PPPoE, ISDN, ATM, etc.).
Routers make their relay decision based on information from the network layer 3 (this is usually the IP address)
or higher. When doing this, many routers also translate between private and public IP addresses (Network
Address Translation, Port Address Translation) or model firewall functions using a set of rules.
Seamless Rate Adaption
Seamless Rate Adaption, possible with ADSL2+, also makes it possible to adapt the transmission speed to the
transmission quality of the cable connection in the case of an existing connection without losing
synchronization (thus without disconnecting the DSL line). This function is not yet implemented at this time
(2010) by German ADSL2+ providers to a large extent (with the exception of HanseNet, QSC and M-net
DSLAMs).
SES
−3
Severely Errored Second: a second with a bit error rate of
≥
1 · 10 .
SNR
(signal-to noise ratio)
The signal-to-noise ratio is a measure of the technical quality of the desired signal (for example, voice or video)
onto which a noise signal is superimposed. It is defined as the ratio of the average power of the desired signal
to the average power of the noise signal.
SIP
The Session Initiation Protocol (SIP) is a network protocol for initiating, controlling and terminating a
communication session between two or more users. The protocol is specified in RFC 3261, among others. In
IP telephony, SIP is a frequently used protocol.
TE
Terminal Equipment, a designation for data terminal equipment that is often used.
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