User's Manual

NETWORKING BASICS
001-9193-001 Version 2 Page 13 of 52 Sentry 4G
TM
User
Manual
3. Networking basics
3.1 General Networking Definitions
The Sentry 4G router is based on Ethernet connectivity and follows general IP networking
guidelines and terminology. Below are definitions of some basic network terminology as they
pertain to the Sentry 4G environment.
Term
Definition
BTS
Base Transceiver Station, fixed equipment that incorporates all radio-
intelligence functions controlling the 802.16-2005 link with one or more Sentry
4G routers.
CINR
Carrier to Interference-plus-Noise Ratio, expressed in decibels (dBs), is a
measurement of signal effectiveness. It provides information on how strong the
desired signal is compared to the unwanted energy (interference plus noise).
DNS
Domain Name System: operates like a phone book to translate domain names
(i.e., google.com) to IP addresses (70.212.19.1).
The Sentry 4G unit functions as the DNS Server in the network.
DHCP
Dynamic Host Configuration Protocol: the DHCP server assigns IP addresses,
gateway and subnet masks to all clients on the network.
The Sentry 4G unit functions as a DHCP Server.
Dynamic/Static IP
A device with Dynamic IP selected may have a different IP address every time
it connects to the network. A device with a Static IP will always connect with
the same IP address.
EAP-TTLS
(Extensible
Authentication
Protocol-Tunneled
Transport Layer
Security)
A universal authentication framework frequently used in wireless networks and
Point-to-Point connections. EAP-TTLS is an EAP method that encapsulates a
TLS session, consisting of a handshake phase and a data phase. During the
handshake phase, the server is authenticated to the client using standard TLS
procedures, and keying material is generated in order to create a
cryptographically secure tunnel for information exchange in the subsequent
data phase. During the data phase, the client is authenticated to the server
using an arbitrary authentication mechanism encapsulated within the secure
tunnel.
Gateway
A (node) device enabling data transfer between different networks (i.e., from a
private LAN to a public WAN).
LAN
Local Area Network. A private network.
MIMO
Multiple Input Multiple Output. MIMO algorithms send information out over two
or more antennas; the information is received via multiple antennas as well.
This use of multiple antennas at both the transmitter and receiver provides a
significant capacity gain over conventional single antenna systems and/or
a more reliable communication.
NAT
Network Address Translation: A technology that allows hosts on the LAN with
private IP addresses to communicate with public IP addresses on the WAN.
This is an essential function of a network router.
OFDM
Orthogonal Frequency Division Multiplexing. 802.16-2005 being a wide area
network is very sensitive to interference and multi-path fading. OFDM
addresses these problems by partitioning the data stream into multiple
narrowband transmissions in the frequency domain using subcarriers that are
orthogonal to one another (do not interfere). These subcarriers are then
reassembled for over-the-air retransmission.
OFDMA
Orthogonal Frequency Division Multiple Access. Allows OFDM to serve many
terminals. Each terminal will be assigned a subset of the subcarrier set for a