+POTS (Plain Old Telephone Service) refers to the standard telephone service that most homes use. In contrast, telephone services based on high-speed, digital communications lines, such as ISDN and FDDI, are not POTS. The man distinctions between POTS and non-POTS services are speed and bandwidth. POTS is generally restricted to about 52 Kbps (52000 bits per second). The POTS network is also called the public switched telephone network (PSTN).
+dial-up access refers to connecting a device to a network via a modem and a public telephone network. The maximum data rate was 56 Kbps.
+leased line is a permanent connection between two devices. Leased lines provide faster throughput and better quality connections, but they are also more expensive.
+ISDN (Integrated Service Digital Network) an international communications standard for sending voice, video, and data over digital telephone lines or normal telephone wires. ISDN supports data transfer rates of 64 Kbps (64000 bits per second). It employs baseband transmission.
+B-ISDN uses broadband transmission and is able to support transmission rates of 1.5 Mbps.
+IDSL (ISDN Digital Subscriber Line) a method of providing DSL technology over existing ISDN lines. Even though the transfer rates for IDSL are about the same as ISDN (144 kbps v. 128 kbps), and IDSL circuits typically only carry data (not voice), the major benefits of switching to IDSL from ISDN are always-on connections, thus eliminating call setup delays; flat rate billing, instead of per minute fees; and transmission of data over the data network, rather than the PSTN.
+xDSL: referes collectively to all types of digital subscriber lines. It is similar to ISDN inasmuch as both operate over existing copper telephone lines (POTS) and both require the short runs to a central telephone office (usually less than 20000 feet). However, xDSL offers much higher speeds - up to 32 Mbps for upstream traffic, and from 32 Kbps to over 1Mbps for downstream traffic.
-ADSL (Asymmetric DSL) is a type of DSL broadband communication technology used for connecting to the Internet. ADSL requires a special ADSL modem and subscribers must be in close geographical locations to the provider's central office to receive ADSL service. ADSL supports data rates of from 1.5 to 9 Mbps when receiving data (known as the downstream rate) and from 16 to 640 Kbps when sending data (known as the upstream rate).
-SDSL (Symmetric DSL) requires a special SDSL modem, it supports the same data rates for upstream and downstream traffic. SDSL supports data rates up to 3 Mbps.
-HDSL (High-data-rate DSL)
-VDSL (Very High DSL) transmits data in the 13 Mbps - 55 Mbps range over short distances, usually between 1000 and 4500 feet (300 - 1500 meters), of twisted pair copper wire. The shorter the distance, the faster the connection rate.
-PaDSL (Private Access DSL) is a solution for creating secure private broadband VPNs. It is most useful to business or organizations who wants to use DSL as an access technology for WAN/VPN objectives without the inherent risk of using the public Internet as the access medium.
+broadband: the term broadband is used to describe a type of data transmission in which a single medium (wire) can carry several channels at once. Cable TV, for example, uses broadband transmission. In contrast, baseband transmission allows only one single at a time.
+throughput: the amount of data transferred from one place to another or processed in a specified amount of time. Data transfer rates for disk drives and networks are measured in terms of throughput. Typically, throughputs are measured in kbps, Mbps and Gbps.
+data transfer rate: the speed with which data can be transmitted from one device to another. Data rates are often measured in megabits (million bits) or megabits (million bytes) per second. These are usually abbreviated as Mbps and MBps, respectively. Another term of data transfer rate is throughput.
+bandwidth: is the amount of data that can be transmitted in a fixed amount of time. For digital devices, the bandwidth is usually expressed in bits per second (bps) or bytes per second. For analog devices, the bandwidth is expressed in cycles per second, or Hertz (Hz).
+bandwidth vs throughput vs latency
+mobile broadband: the phrase used to describe Internet access (wireless communications) that is obtained through a portable modem or other device, such as a mobile phone. It is typically used by a wireless carriers to describe its mobile Internet access service that uses the mobile phone infrastructure, or cellular network. A number of network standards can be used for mobile broadband including:
-GSM (Global Sstem for Mobile Communications) 9.6 Kbps
-GPRS (General Packet Radio Service) 115 Kbps
-EDGE (Enhanced Data GSM Environment) 384 Kbps
-3G
-WiMAX
-UMTS (Universal Mobile Telecommunications System)
-HSPDA (High Speed Downlink Packet Access)
-HSUPA (High Speed Uplink Packet Access)
CDMA (Code-Division Multiple Access)
TDM (Time-division multiplexing)
CDMA vs TDM
TDMA (Time Division Multiple Access)
PPPoE (Point-to-Point Protocol over Ethernet) relies on two widely accepted standards: PPP and Ethernet. PPPoE is a specification for connecting the users on an Ethernet to the Internet through a common broadband medium, such as a single DSL line, wireless device or cable modem. All the users over the Ethernet share a common connection, so the Ethernet principles supporting multiple users in a LAN combine witht the principles of PPP, which apply to serial connections.
+CAM (Channel Access Method) a protocol for how data is transmitted in the bottom two layers of the OSI model. CAMs describe how networking systems put data on the network media, how low-level errors are dealt with, and how the network policies itself. Polling, contention and token passing are three examples of CAMs.
-CSMA/CD (Carrier Sense Multiple Access / Collision Detection)
-Token-ring network: a type of computer network in which all the computers are arranged (schematically) in a circle. A token, when is a special bit pattern, travels around the circle. To send a message, a computer catches the token, attaches a message to it, and then lets it continue to travel around the network.
-token passing: a type of CAM. Token passing uses a token, or series of bits, to grant a device permission to transmit over the network. Whichever device has the token can put data into the network. When its transmission is complete, the device passes the token along to the next device in the topology. System rules in the protocol specifications mandate how long a device may keep the token, how long it can transmit for and how to generate a new token if there isn't one circulating.
-polling: is a CAM. In a master/slave scenario, the master queries each slave device in turn as to whether it has any data to transmit. If the slave answers yes then the device is permitted to transmit its data. If the slave answers no then the master moves on and polls the next slave device. The process is repeated continuously.
-contention: a type of network protocol that allows nodes to contend for network access. That is, two or more nodes may try to send messages across the network simultaneously. The contention protocol defines what happens when this occurs. The most widely used contention protocol is CSMA/CD, used by Ethernet.
+Ethernet: a LAN architecture developed by Xerox Corporation in cooperation with DEC and Intel in 1976. Ethernet uses a bus or star topology and supports data transfer rate of 10 Mbps. The Ethernet specification served as the basic for the IEEE 802.3 standard, which specifies the physical and lower software layers. Ethernet uses the CSMA/CD access method to handle simultaneous demands. It is one of the most widely implemented LAN standards.
+100Base-T (or Fast Ethernet) a newer version of Ethernet supports data transfer rates of 100 Mbps.
+Gigabit Ethernet a newest version of Ethernet supports data transfer rates of 1 gigabit (1000 megabits) per second.
+Types of Internet Connections
-Analog: Dial-up Internet Access
-ISDN (Integrated Services Digital Network)
-B-ISDN (Broadband ISDN)
-DSL (Digital Subscriber Line)
-ADSL (Asymmetric Digital Subscriber Line)
-ADSL+2 (ADSL Extension)
-SDSL (Symmetric Digital Subscriber Line)
-VDSL (Very High DSL)
-Cable (Broadband Internet Connection)
-Wireless Internet Connections
-T-1 Lines (Leased Line)
-Bonded T-1
-T-3 Lines (Dedicated Leased Line)
-OC3 (Optical Carrier)
-Internet over Satellite
+Network Topology
-Mesh Topology
-Star Topology
-Bus Topology
-Ring Topology
-Tree Topology
+VPN (Virtual Private Network) is a network that is constructed by using public wires - usually the Internet - to connect to a private network, such as a company's internal network. There are a number of systems that enable you to create networks using the Internet as the medium for transporting data. These systems use encryption and other security mechanisms to ensure that only authorized users can access the network and that the data cannot be intercepted.
+shared hosting
+VPS (virtual private server)
+dedicated server hosting: as a dedicated server client you rent an entire dedicated server from us. We remain the oner of the physical server, but you get complete control over the content and built.
+colocation: you rent space in data centres to securely house your IT hardware, whilst retaining full ownership and complete control.
+reseller
parked domain
domain parking
multi websites
Unlimited Hosted Domains
Unlimited Bandwidth
1 dedicated IP address
Public IPs
+RIR (Regional Internet Registry)
Why RIRs are needed.
Yes, there are millions of IP addresses available, but that number is not limitless. The current version of the IP address (technically known as IPv4) does not have an infinite number of addresses available. That fact made the Internet administration organizations realize there was an urgent need for up-close and smart management of the inventory of IP addresses. Put another way, the IP world realized there had to be enough IP addresses to go around for everyone, and a system for allocating them efficiently.
The RIR came up with guidelines to make it all work. Each individual RIR is required to follow a neutral policy of IP address allocation and distribution. That helps prevent one RIR from hoarding IP addresses for computer users in its geographical region or doing anything to put other regions at a disadvantage. After all, without ongoing access to IP addresses—which allows people to connect with other users locally and worldwide—a network is doomed.
The Role of the RIR.
The RIRs, as a matter of fact, do not generate the IP addresses that they themselves allocate. The Internet Assigned Numbers Authority (IANA) is the Internet organization that allocates IP addresses to each RIR, which takes it from there, handling the next level of allocation. An RIR serves:
Large regional entities, including Internet Service Providers (ISPs)
Educational institutions
Governments
Large corporation and organizations
RIR meets NRO.
All five RIRs combined to form the Number Resource Organization (NRO). The NRO was needed to help the RIRs coordinate technical and policy initiatives among themselves and to ensure that the RIRs could work seamlessly together. The mission of the NRO is to:
Keep tabs on the IP address resource pool, protecting available IP addresses
Protect and promote the policies of the Internet
Serve as a focal point for input from the Internet communities in each RIR
-ARIN (American Registry for Internet Numbers)
-LACNIC (Latin American and Caribbean Internet Address Registry)
-RIPE NCC (R�seaux IP Europ�ens Network Coordination Centre)
-AfriNIC (The African Network Information Centre)
-APNIC (The Asia-Pacific Network Information Centre)
The IP Transit service provides global Internet access for Licensed Telecom Operators with an Autonomous System (AS) Number obtained from APNIC.
