Comtech EF Data MDX420 SkyWire Manual - Manual (Page 120)

MDX420 SkyWire™ Satellite Network Gateway SkyWire QoS
MN-MDX420 Revision 6 C–10
C.4.6 Auto Everything Ethernet ports
The auto crossover, auto polarity, auto negotiation functionality on the SkyWire Ethernet ports
provide true “plug and play” connectivity and eliminates the need for special cabling.
C.4.6.1 Auto Crossover
SkyWire automatically determines whether or not it needs to cross over between pairs so that
external crossover cables are not required. When interoperating with a device that can’t
automatically adjust for crossover, Skywire makes the necessary adjustments prior to
commencing auto-negotiation. When interoperating with a device that implements MDI/MDIX
crossover, a random algorithm as described in IEEE 802.3 section 40.4.4 determines which
device performs the crossover.
C.4.6.2 Auto Polarity
SkyWire automatically detects and corrects for polarity errors on the receive pairs in 1000Base-T
and 10Base-T modes. In 100Base-T mode, the polarity does not matter.
C.4.6.3 Auto Negotiation
SkyWire automatically negotiates with its link partner to determine the speed and duplex at which
to operate. If the link partner is unable to auto-negotiate, SkyWire utilizes a parallel detect mode
to determine the speed of the link partner and then operates in half-duplex at the appropriate
rate.
C.4.6.4 Transparent Operation
Because SkyWire is completely transparent to the applications that are being run, you don’t have
to worry about whether or not they will work over SkyWire. The answer is yes. Whether it’s a
VoIP call, or a DHCP server application, or a VPN to the office to check e-mail, or simply web-
surfing, if it’s transmitted via Ethernet, it will pass transparently though SkyWire from one point to
another.
C.4.7 Adding Acceleration, Compression, Network Security, and Traffic
Shaping
Today, there are various acceleration, compression, IP security, and traffic shaping solutions
available from numerous third party vendors. Some are proprietary implementations, while others
are based on open standards such as MIL-STD-2045-44000 and CCSDS 714.0-B-1. Some may
even be implemented in your current network and routers. And while different solutions (including
none at all) make sense for different types of networks, SkyWire, with its transparent mode of
operation is compatible with all of them.