D-Link DSL 2740B - Manual (Page 39)

DSL-2740B Wireless ADSL Router User Guide
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by bursts of packets at variable intervals, and some moderate packet loss
and delay is acceptable. This category is typically used for audio and video
applications such as teleconferencing. The network must support QoS Class
2 to use VBR.
PCR
Peak Cell Rate – The PCR is inversely related to the time interval between
ATM cells. It is specified for all three service categories (UBR, CBR and
VBR) in Kbps.
SCR
Sustainable Cell Rate – The SCR is defined for the VBR service category.
This is the rate that can be sustained for “bursty”, on-off traffic sources. It
is a function of Maximum Burst Size (MBS) and the time interval (between
cells).
CDVT
Cell Delay Variation Tolerance – CDVT is a measure of the cell clumping
phenomenon by which cells are delayed in the network and are
clumped together and arrive at a system at a faster rate than negotiated.
Increasing the CDVT creates greater bucket depth.
MBS
Maximum Burst Size – The MBS is the maximum number of bytes that can
be sent continuously from the source to the destination dropping any
packets. Some ATM providers set the MBS and CDVT very low and adjust
up if problems occur.
Router Settings:
Parameters Description
Default Route When this is enabled, the Router will be considered to be the primary
gateway to the Internet and WAN for systems on your network. If you
are using the Router on a network with one or more alternative gateway
routers, you may prefer to disable this if you will use another router as
the primary gateway.
NAT Network Address Translation may be enabled or disabled with the pull-
down menu. Keep in mind that disabling NAT allows only a single
computer to be used for Internet access through the Router. NAT is
enabled and disabled for the Router on all connections (i.e. Pvc0 – Pvc7)
if your Router is set up for multiple virtual connections.
Firewall Use this to universally enable or disable the Firewall and Filter features
available in the Router. If you disable this you will not be able to
configure settings in the Firewall Configuration window or Filters
window in the Advanced directory.
Primary DNS Address This is the IP address of the first choice for Domain Name Service (DNS)
used to match the named URL web address used by most browsers with
the actual global IP address used for a web server. Usually this will be a
server owned by the ISP. Get this IP address from your ISP.
Secondary DNS Address This is the second choice for a DNS server. Get this IP address from
your ISP.