TOPEX Bytton (HSPA+ / LTE)
ByttonLTE(full)_genericUsermanual_sw306FAS_revN.1.docx
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Denny acts in reverse, the clients with specified MACs will be rejected, while all others are allowed
access. This is useful when you know that some computers may have viruses and want to prevent the
infection from spreading!
Of course, some wireless clients allow their MAC address to be "impersonated" or "spoofed" in software.
It's certainly possible for a hacker to break into your WLAN by configuring their client to spoof one of
your allowed MAC addresses. Thus a determined attacker could capture details about MAC addresses
from your network and pretend to be that device to connect to VLAN via Bytton. Although MAC address
filtering isn't bulletproof, still it remains a helpful additional layer of defense that improves overall Wi-Fi
network security against casual hackers or curious snoopers.
MIMO
(Multiple-input, multiple-output) technique has been established for mobile data communications as
early as 1996. In the beginning the MIMO applications were targeted towards useage with WiFi and
WiMAX local networks, since it was much easier to integrate MIMO into emerging devices, than into the
3G market where the standards were already established. But in the meantime the expanding standard
3G LTE (long-term evolution) has adopted MIMO and is on the rise. This is why MIMO or dual-antenna
technique can be used
both on the WLAN and WWAN sides of Bytton LTE!
MTU
- Acronym for Maximum Transmission Unit. Generally, the size of the largest datagram that can be
passed by a layer of a communications protocol (that can be transmitted or received through a logical
interface). All messages larger than the MTU will be divided into smaller packets before being sent. In our
case MTU is the largest physical packet size, measured in bytes that a network can transmit. The size
includes the IP header but does not include the size of any Link Layer headers or framing. Thus, when
encapsulation and additional headers are used, you must take into account the additional length
generated.
Different networks have different values for MTU, which is set by the network administrator. Most
networking technologies have a default MTU size: this is 576 for many PPP connections, 1500 for
Ethernet networks, 65K for HYPER channel, etc. This is why the Web interface of Bytton LTE lets you to
configure specific MTU values for each interface.
NAT
- Network Address Translation. NAT is an Internet standard that enables a local-area network (LAN)
to use one set of IP addresses for internal traffic and another set of addresses for external traffic. On the
gateway, NAT software performs all necessary translations of the IP addresses. There are several
purposes for NAT usage: it provides a type of natural firewall by hiding all the internal IP addresses from
the Internet. Only the single IP assigned to the router is visible from the Internet. Several computers on the
local network to use one IP address, enabling access to the Internet from any computer network without
the need to get more IP addresses from the ISP. Also, local computers are not directly reachable from the
Internet, making them more secure. With NAT, the company can use several internal IP addresses. Since
they're used only internally, there is no possibility of conflict with IP addresses used by other companies or
organizations. Bytton allows you to selectively enable NAT or Masquerading for each of its interfaces!
NTP -
Acronym for
N
etwork
T
ime
P
rotocol. Internet standard protocol used to update the real-time clock in
a computer. It assures accurate synchronization to the millisecond of computer clock times in a network of
computers. NTP is very useful in packet-switched, variable-latency data networks.
In case of Bytton LTE, when you want to measure the performances of the network, you need accurate,
universal time-stamps for the data packets.
NTP runs as a continuous background client program on a computer and it sends periodic time requests
to servers, obtaining server time stamps and using them to adjust the client's clock. NTP uses UDP port
123 as its transport layer. It is designed particularly to resist the effects of variable latency. There are
numerous primary and secondary servers in the Internet that are synchronized to the Coordinated
Universal Time (UTC) via radio, satellite or modem. For more information, visit
www.ntp.org
.
PPP
- Acronym for Point-to-Point Protocol. Network protocol widely used to connect computers to the
Internet. Works on the data link layer of the OSI model. PPP sends the TCP/IP packets of the gateway to
a server that puts them onto the Internet. It is more stable than the older SLIP protocol and provides error-
checking features.
PPP is the Internet standard for dial-up modem connections, no matter if they are phone line modems of
high-speed UMTS wireless devices such as the embedded HSPA or LTE modem of Bytton LTE.
PPPoE
- Acronym for Point-to-Point Protocol over Ethernet. A method of secure data transmission,
PPPoE using Ethernet to connect to an ISP. The PPP traffic is sent over Ethernet to the Internet through a
common broadband medium. The users have the appearance of "dialing" the Internet, but their computers
are in fact always connected.
