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The Internet Domain name industry didn't have too bad of a year in 2009, even as the global economic downturn raged. According to the latest Domain Name Industry Brief from VeriSign, the total base of registered Top-Level Domain Names (TLDs) grew in 2009.

VeriSign reported that in 2009, the base of TLDs expanded by 15 million domains names to a total of 192 million domain registration across all TLDs.

Helping to the lead the way were the .com and .net TLDs, which at the end of 2009 accounted for 96.7 million domain names. The 2009 tally represents a 7 percent increase over the total number of .com and .net TLDs at the end of 2008. The company also said that that during the fourth quarter of 2009 alone, it added 7.3 million new .com and .net registrations. VeriSign manages both the .com and .net registries under contract from ICANN.

The growth isn't the only milestone for the .com domain. On March 15, VeriSign will celebrate the 25th anniversary of the first .com name -- Symbolics.com -- which was assigned in 1985.

The .com and .net domain names aren't the only ones that are growing. The total number of country code Top-Level Domains (ccTLDs) also continued to rise in 2009. In total, VeriSign reported that there were 78.6 million ccTLD at the end of 2009, an increase of 7.5 million domain names from 2008.

Overall, there are now more than 240 ccTLDs in use, with China's .cn remaining the most popular ccTLD, followed by Germany's .de and the United Kingdom's .uk.

While China has been the top ccTLD since the third quarter of 2008, the rate of growth in the .cn ccTLD has actually slowed.

"The .cn base, which had been experiencing remarkable growth as high as 467 percent year over year, slowed its growth and ended the fourth quarter with a one percent decline in its base," VeriSign's report stated.

Sitting behind all those domain names is the global DNS (define) system, which VeriSign helps to administer. As domain names have grown, so too has the load on the DNS system. VeriSign reported that during the fourth quarter of 2009, it hit peaks of 61 billion DNS queries per day. Average daily DNS query load amounted to 52 billion per day, which is an increase of 48 percent over the same period in 2008.

In 2009, VeriSign improved its DNS capabilities by way of its $100 million project Titan, an effort to improve capacity by a factor of 10.

source:http:enterprisenetworkingplanet.com

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The Internet Protocol (IP) is a protocol used for communicating data across a packet-switched internetwork using the Internet Protocol Suite, also referred to as TCP/IP.

IP is the primary protocol in the Internet Layer of the Internet Protocol Suite and has the task of delivering distinguished protocol datagrams (packets) from the source host to the destination host solely based on their addresses. For this purpose the Internet Protocol defines addressing methods and structures for datagram encapsulation. The first major version of addressing structure, now referred to as Internet Protocol Version 4 (IPv4) is still the dominant protocol of the Internet, although the successor, Internet Protocol Version 6 (IPv6) is being deployed actively worldwide.

IP encapsulation

Data from an upper layer protocol is encapsulated as packets/datagrams (the terms are basically synonymous in IP). Circuit setup is not needed before a host may send packets to another host that it has previously not communicated with (a characteristic of packet-switched networks), thus IP is a connectionless protocol. This is in contrast to public switched telephone networks that require the setup of a circuit for each phone call (connection-oriented protocol).

Services provided by IP

Because of the abstraction provided by encapsulation, IP can be used over a heterogeneous network, i.e., a network connecting computers may consist of a combination of Ethernet, ATM, FDDI, Wi-Fi, token ring, or others. Each link layer implementation may have its own method of addressing (or possibly the complete lack of it), with a corresponding need to resolve IP addresses to data link addresses. This address resolution is handled by the Address Resolution Protocol (ARP) for IPv4 and Neighbor Discovery Protocol (NDP) for IPv6.

Reliability

The design principles of the Internet protocols assume that the network infrastructure is inherently unreliable at any single network element or transmission medium and that it is dynamic in terms of availability of links and nodes. No central monitoring or performance measurement facility exists that tracks or maintains the state of the network. For the benefit of reducing network complexity, the intelligence in the network is purposely mostly located in the end nodes of each data transmission, cf. end-to-end principle. Routers in the transmission path simply forward packets to next known local gateway matching the routing prefix for the destination address.

As a consequence of this design, the Internet Protocol only provides best effort delivery and its service can also be characterized as unreliable. In network architectural language it is a connection-less protocol, in contrast to so-called connection-oriented modes of transmission. The lack of reliability allows any of the following fault events to occur:

• data corruption
• lost data packets
• duplicate arrival
• out-of-order packet delivery; meaning, if packet 'A' is sent before packet 'B', packet 'B' may arrive before packet 'A'. Since routing is dynamic and there is no memory in the network about the path of prior packets, it is possible that the first packet sent takes a longer path to its destination.

The only assistance that the Internet Protocol provides in Version 4 (IPv4) is to ensure that the IP packet header is error-free through computation of a checksum at the routing nodes. This has the side-effect of discarding packets with bad headers on the spot. In this case no notification is required to be sent to either end node, although a facility exists in the Internet Control Message Protocol (ICMP) to do so.

IPv6, on the other hand, has abandoned the use of IP header checksums for the benefit of rapid forwarding through routing elements in the network.

The resolution or correction of any of these reliability issues is the responsibility of an upper layer protocol. For example, to ensure in-order delivery the upper layer may have to cache data until it can be passed to the application.

In addition to issues of reliability, this dynamic nature and the diversity of the Internet and its components provide no guarantee that any particular path is actually capable of, or suitable for performing the data transmission requested, even if the path is available and reliable. One of the technical constraints is the size of data packets allowed on a given link. An application must assure that it uses proper transmission characteristics. Some of this responsibility lies also in the upper layer protocols between application and IP. Facilities exist to examine the maximum transmission unit (MTU) size of the local link, as well as for the entire projected path to the destination when using IPv6. The IPv4 internetworking layer has the capability to automatically fragment the original datagram into smaller units for transmission. In this case, IP does provide re-ordering of fragments delivered out-of-order.

Transmission Control Protocol (TCP) is an example of a protocol that will adjust its segment size to be smaller than the MTU. User Datagram Protocol (UDP) and Internet Control Message Protocol (ICMP) disregard MTU size thereby forcing IP to fragment oversized datagrams.

IP addressing and routing

Perhaps the most complex aspects of IP are IP addressing and routing. Addressing refers to how end hosts become assigned IP addresses and how subnetworks of IP host addresses are divided and grouped together. IP routing is performed by all hosts, but most importantly by internetwork routers, which typically use either interior gateway protocols (IGPs) or external gateway protocols (EGPs) to help make IP datagram forwarding decisions across IP connected networks

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Satellites have brought Internet access to places where IP communications seemed impossible. In this section, we explain how satellite Internet works. You will understand how bytes of information or simply a mouse click travels all the way from your computer to the satellite, to our NOC and back.

VSAT Systems uses commercial satellite connections as a high-speed digital link between our customers and the U.S. Internet backbone. The main components of a satellite system comprises of the following:

1. Ground-based electronic equipment

• The VSAT dish: It refers to what most people call their dish. VSAT units are two-way satellite ground stations with dishes that typically range from 0.75m to 1.8m in diameter. VSAT Systems offers VSAT antennas between 1.2m and 2.4m in diameter, depending on the application and location.
• The indoor modem: A satellite modem facilitates data transfers using a communications satellite as a relay. VSAT Systems end users typically use the iDirect 3100 series Modem.
• The teleports: The teleport is the earth station that controls communications across the space link. The teleport is the heart of the VSAT Systems satellite Internet system. VSAT Systems has three 6.3m VertexRSI antennae, transmitters, control systems, redundant links to the Internet, plus auxiliary power and HVAC.
• The Network Operations Center (NOC): The facility which controls all communications over the satellite link. The NOC monitors for power failures, satellite signal issues and other performance issues that may affect the network. The VSAT Systems NOC is located in Akron, Ohio.

2. Satellite equipment

• The satellite: In a geostationary or geosynchronous orbit 22,236 miles above the earth’s surface, a satellite completes one revolution in exactly the same amount of time that it takes the Earth to rotate one full turn on its axis. Thus, the satellite always appears at the same position above the Earth. This eliminates the need for satellite dishes at the user location to track the satellite, which greatly simplifies their construction and cost. These satellites, used for a variety of purposes like broacast and telecommunications, can also be used to provide Internet access at any location on Earth.
• Transponder space segment: The communications channels on a satellite that both receive and retransmit data. Modern satellites carry between 36 and 72 separate transponders all running at different frequencies. These frequency segments are used for transmission of data.
• Internet Backbone: The backbone is a large collection of interconnected, high-capacity, commercial, government, and academic data routes and core routers that carry data. They connect with other countries and continents around the world.

3. Here’s how the process works - in 5 easy to understand steps:

• End user computer is connected to your network, which in turn is connected to the Internet by VSAT Systems. You open a web browser, and type in a web address. End user computer sends a request for a transfer of data - both transmit and receive.
• That request is sent from the end user PC, through their home network, to the indoor satellite modem which modulates the signal and passes it to the VSAT dish. The VSAT dish converts this signal to an RF signal and sends it to a satellite located in the geostationary orbit at the speed of light - 186,000 miles per second.
• The satellite in the geo-stationary orbit receives this signal and sends it to one of the VSAT Systems teleports in Akron, Ohio. This illustrates the fact that although the packets of information travel tremendous distances via the space segment, the packets hop fewer networks due to the large reduction in the number of inter domain and intra domain routers giving an opportunity to minimize latency.
• The request then goes to VSAT Systems’ NOC, which retrieves the requested website from the web server, across the U.S. Internet backbone.
• The whole cycle is then reversed and the requested data is available to the user. A 90,000 mile journey, through millions of dollars of infrastructure and sophisticated equipment, all in less than 700 milliseconds.

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LAS VEGAS--We saw dozens of new laptop models at CES this year, and though the vast majority of them were next-step upgrades of existing models, there were a handful that really grabbed our attention, either because they brought something new to the game, or because they were excellent examples of their category.

We've already rounded up the various slate/tablet devices, so we'll concentrate on traditional laptop-shaped systems (although we'll make an exception for the Lenovo U1 Hybrid, which docks its tablet screen to become a standard Windows 7 machine).

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