Updates: Gadgets 2010

Apple iTablet
Currently, there are some rumors about two new “tablet” projects: Apple iTablet and Microsoft Courier.



As for the Microsoft Courier, apparently, this Tablet PC is in the last stage of development and its features would make it look more like a Booklet than a Tablet PC. Although an official introduction of this device has not been carried out, Microsoft is already studying impressions of some users that have used a Tablet PC, which is a term that refers to computers equipped with a touchscreen (or graphics tablet/screen hybrid) and complex settings, applications and modes.



At the moment it is known that (with regard to the features of the new Microsoft product) it will have a dual 7-inch display with multitouch support where the user will be able to turn over pages, write, and draw by using the fingers or a stylus pen. The display also will show the battery level and the internet connection status on a side area. In addition, the Microsoft Courier will come with a photo camera on the back of the device, but it is unknown how many pixels will be featured.

Patch Panel and Modular Jacks

There are Passive Components that are unfamiliar to IT professionals and even to Industry related personnel.

patch panel or patch bay is a panel, typically rackmounted, that houses cable connections.
Diagram:

Sample Image:


Modular Jacks
Modular jack connectors, a cornerstone of communications technology, have been used in the telecommunications and ethernet industry for many years. The main reasons for this are the simplicity and reliability of these products. Whether integrated in a simple telephone system, or in a gigabit application, “mod. jacks” represent the standard for network connections. Mod. jacks can be obtained in many different versions. Increasing data rates and space-saving requirements are driving increasing requests for these connectors with integrated filter components.
Modular Jacks:

Differentiating Routers and Switches

As for switches, it's main function is to only connect networking segments to create communication between nodes through computer gateways like the Ethernet. Switches commonly processes data at the OSI layer 2 or the data link layer. Since Switches typically transfers data from interconnected nodes in a networked area. Switches is a Point-to-Point or Point-to-Multipoint data transfer and a PPP or Point to Point Protocol.

Switch

While Routers are the kind of Active networking Component that connects multiple extended networks together. It sends packets of data from multiple sources and sends it to addressed destinations.

Router


That is Routers belongs to the Layer of the OSI Layer (Networking Layer). It transfers length of data from point-to-destination via one or more networks with quality service required by the transport layer.

In Conclusion, as what I've understood--Switches are for LAN purposes or distribution for internet connection since it is only concerned with the Layer 2 of the OSI model which is the Data Link Layer or transferring of data.
And Routers are more to network-to-network (WAN or MAN) connectivity rather than LAN.

Routers

For us to differentiate Routers to Switches, read.

Routers are physical devices that join multiple wired or wireless networks together. Technically, a wired or wireless router is a Layer 3 gateway, meaning that the wired/wireless router connects networks (as gateways do), and that the router operates at the network layer of the OSI model.
More technically, a router is a networking device whose software and hardware are usually tailored to the tasks of routing and forwarding information. Routers connect two or more logical subnets, which do not necessarily map one-to-one to the physical interfaces of the router. The term "layer 3 switching" is often used interchangeably with routing, but switch is a general term without a rigorous technical definition. In marketing usage, a switch is generally optimized for Ethernet LAN interfaces and may not have other physical interface types. In comparison, the network hub (predecessor of the "switch" or "switching hub") does not do any routing, instead every packet it receives on one network line gets forwarded to all the other network lines.

Home networkers often use an Internet Protocol (IP) wired or wireless router, IP being the most common OSI network layer protocol. An IP router such as a DSL or cable modem broadband router joins the home's local area network (LAN) to the wide-area network (WAN) of the Internet.

Routers operate in two different planes:
* Control plane, in which the router learns the outgoing interface that is most appropriate for forwarding specific packets to specific destinations,
* Forwarding plane, which is responsible for the actual process of sending a packet received on a logical interface to an outbound logical interface.

Routers may provide connectivity inside enterprises, between enterprises and the Internet, and inside Internet Service Providers (ISPs). The largest routers (for example the Cisco CRS-1 or Juniper T1600) interconnect ISPs, are used inside ISPs, or may be used in very large enterprise networks. The smallest routers provide connectivity for small and home offices.
[edit] Routers for Internet connectivity and internal use

Routers intended for ISP and major enterprise connectivity will almost invariably exchange routing information with the Border Gateway Protocol (BGP). RFC 4098[3] defines several types of BGP-speaking routers:

* Edge Router: Placed at the edge of an ISP network, it speaks external BGP (eBGP) to a BGP speaker in another provider or large enterprise Autonomous System(AS) .
* Subscriber Edge Router: Located at the edge of the subscriber's network, it speaks eBGP to its provider's AS(s). It belongs to an end user (enterprise) organization.
* Inter-provider Border Router: Interconnecting ISPs, this is a BGP speaking router that maintains BGP sessions with other BGP speaking routers in other providers' ASes.
* Core router: A router that resides within the middle or backbone of the LAN network rather than at its periphery.

Within an ISP: Internal to the provider's AS, such a router speaks internal BGP (iBGP) to that provider's edge routers, other intra-provider core routers, or the provider's inter-provider border routers.
"Internet backbone:" The Internet does not have a clearly identifiable backbone, as did its predecessors. See default-free zone (DFZ). Nevertheless, it is the major ISPs' routers that make up what many would consider the core. These ISPs operate all four types of the BGP-speaking routers described here. In ISP usage, a "core" router is internal to an ISP, and used to interconnect its edge and border routers. Core routers may also have specialized functions in virtual private networks based on a combination of BGP and Multi-Protocol Label Switching (MPLS).
Routers are also used for port forwarding for private servers.

Data Source

Networking SWITCHES

A network switch is a computer networking device that connects network segments.
The term commonly refers to a network bridge that processes and routes data at the data link layer (layer 2) of the OSI model. Switches that additionally process data at the network layer (layer 3 and above) are often referred to as Layer 3 switches or multilayer switches.
The term network switch does not generally encompass unintelligent or passive network devices such as hubs and repeaters.



Function:
The network switch, packet switch (or just switch) plays an integral part in most Ethernet local area networks or LANs. Mid-to-large sized LANs contain a number of linked managed switches. Small office/home office (SOHO) applications typically use a single switch, or an all-purpose converged device such as gateway access to small office/home broadband services such as DSL router or cable Wi-Fi router. In most of these cases, the end user device contains a router and components that interface to the particular physical broadband technology, as in the Linksys 8-port and 48-port devices. User devices may also include a telephone interface to VoIP.

In the context of a standard 10/100 Ethernet switch, a switch operates at the data-link layer of the OSI model to create a different collision domain per switch port. If you have 4 computers A/B/C/D on 4 switch ports, then A and B can transfer data between them as well as C and D at the same time, and they will never interfere with each others' conversations. In the case of a "hub" then they would all have to share the bandwidth, run in Half duplex and there would be collisions and retransmissions. Using a switch is called micro-segmentation. It allows you to have dedicated bandwidth on point to point connections with every computer and to therefore run in Full duplex with no collisions.
Roles:
In the context of a standard 10/100 Ethernet switch, a switch operates at the data-link layer of the OSI model to create a different collision domain per switch port. If you have 4 computers A/B/C/D on 4 switch ports, then A and B can transfer data between them as well as C and D at the same time, and they will never interfere with each others' conversations. In the case of a "hub" then they would all have to share the bandwidth, run in Half duplex and there would be collisions and retransmissions. Using a switch is called micro-segmentation. It allows you to have dedicated bandwidth on point to point connections with every computer and to therefore run in Full duplex with no collisions.

Network switch is a marketing term rather than a technical one.[citation needed] Switches may operate at one or more OSI layers, including physical, data link, network, or transport (i.e., end-to-end). A device that operates simultaneously at more than one of these layers is called a multilayer switch, although use of the term is diminishing.[citation needed]

In switches intended for commercial use, built-in or modular interfaces make it possible to connect different types of networks, including Ethernet, Fibre Channel, ATM, ITU-T G.hn and 802.11. This connectivity can be at any of the layers mentioned. While Layer 2 functionality is adequate for speed-shifting within one technology, interconnecting technologies such as Ethernet and token ring are easier at Layer 3.

Interconnection of different Layer 3 networks is done by routers. If there are any features that characterize "Layer-3 switches" as opposed to general-purpose routers, it tends to be that they are optimized, in larger switches, for high-density Ethernet connectivity.

In some service provider and other environments where there is a need for a great deal of analysis of network performance and security, switches may be connected between WAN routers as places for analytic modules. Some vendors provide firewall,network intrusion detection,and performance analysis modules that can plug into switch ports. Some of these functions may be on combined modules.

In other cases, the switch is used to create a mirror image of data that can go to an external device. Since most switch port mirroring provides only one mirrored stream, network hubs can be useful for fanning out data to several read-only analyzers, such as intrusion detection systems and packet sniffers.

Source

TCP/IP Networking

Although UUCP may be a reasonable choice for low-cost dial-up network links, there are many situations in which its store-and-forward technique proves too inflexible, for example in Local Area Networks (LANs). These are usually made up of a small number of machines located in the same building, or even on the same floor, that are interconnected to provide a homogeneous working environment. Typically, you would want to share files between these hosts, or run distributed applications on different machines.

These tasks require a completely different approach to networking. Instead of forwarding entire files along with a job description, all data is broken up in smaller chunks (packets), which are forwarded immediately to the destination host, where they are reassembled. This type of network is called a packet-switched network. Among other things, this allows to run interactive applications over the network. The cost of this is, of course, a greatly increased complexity in software.

For something concrete to look at as we discuss TCP/IP throughout the following sections, we will consider Groucho Marx University (GMU), situated somewhere in Fredland, as an example. Most departments run their own local area networks, while some share one, and others run several of them. They are all interconnected, and are hooked to the Internet through a single high-speed link.

Suppose your box is connected to a LAN of hosts at the Mathematics Department, and its name is erdos. To access a host at the Physics Department, say quark, you enter the following command:

$ rlogin quark.physics
Welcome to the Physics Department at GMU
(ttyq2) login:

At the prompt, you enter your login name, say andres, and your password. You are then given a shell on quark, to which you can type as if you were sitting at the system's console. After you exit the shell, you are returned to your own machine's prompt. You have just used one of the instantaneous, interactive applications that TCP/IP provides: remote login.