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Showing posts with label networking. Show all posts
Showing posts with label networking. Show all posts

Cloud Computing

Fahmi Rizwansyah says:

by some resources

Cloud computing provides a cost-effective architecture that has enabled new business models including Platform-as-a-Service (Paas) and Software-as-a-Service (SaaS). The financial crisis might spell good news for cloud providers up and down the stack. According recent articles, IDC predicts that the current economic crisis in the U.S. will contribute to cloud computing growth over the next five years and spending on IT cloud services will reach $42 billion by 2012. Frank Gens, senior vice president and chief analyst at IDC believes, "The disruptive vectors of the market will be among the highest growth sectors in 2009 as their advantages are magnified in a down economy, and suppliers who slow down their transformation will limit long-term viability and miss near-term growth."


John Horrigan at Pew Research offered this look at cloud adoption in the consumer space, which has been driving the growth of the big public platforms long before the economic downturn. As IT organizations are pressured to find yet more efficiency it will be interesting to see how quickly they find the confidence in providers to follow consumers to the cloud. At a snap poll of attendees conducted this week at Gartner’s Data Center Conference the results appear promising.

Cloud computing comes into focus only when you think about what IT always needs: a way to increase capacity or add capabilities on the fly without investing in new infrastructure, training new personnel, or licensing new software. Cloud computing encompasses any subscription-based or pay-per-use service that, in real time over the Internet, extends IT's existing capabilities.

Cloud computing is at an early stage, with a motley crew of providers large and small delivering a slew of cloud-based services, from full-blown applications to storage services to spam filtering. Yes, utility-style infrastructure providers are part of the mix, but so are SaaS (software as a service) providers such as Salesforce.com. Today, for the most part, IT must plug into cloud-based services individually, but cloud computing aggregators and integrators are already emerging.

InfoWorld talked to dozens of vendors, analysts, and IT customers to tease out the various components of cloud computing. Based on those discussions, here's a rough breakdown of what cloud computing is all about:

1. SaaS
This type of cloud computing delivers a single application through the browser to thousands of customers using a multitenant architecture. On the customer side, it means no upfront investment in servers or software licensing; on the provider side, with just one app to maintain, costs are low compared to conventional hosting. Salesforce.com is by far the best-known example among enterprise applications, but SaaS is also common for HR apps and has even worked its way up the food chain to ERP, with players such as Workday. And who could have predicted the sudden rise of SaaS "desktop" applications, such as Google Apps and Zoho Office?

2. Utility computing
The idea is not new, but this form of cloud computing is getting new life from Amazon.com, Sun, IBM, and others who now offer storage and virtual servers that IT can access on demand. Early enterprise adopters mainly use utility computing for supplemental, non-mission-critical needs, but one day, they may replace parts of the datacenter. Other providers offer solutions that help IT create virtual datacenters from commodity servers, such as 3Tera's AppLogic and Cohesive Flexible Technologies' Elastic Server on Demand. Liquid Computing's LiquidQ offers similar capabilities, enabling IT to stitch together memory, I/O, storage, and computational capacity as a virtualized resource pool available over the network.

3. Web services in the cloud
Closely related to SaaS, Web service providers offer APIs that enable developers to exploit functionality over the Internet, rather than delivering full-blown applications. They range from providers offering discrete business services -- such as Strike Iron and Xignite -- to the full range of APIs offered by Google Maps, ADP payroll processing, the U.S. Postal Service, Bloomberg, and even conventional credit card processing services.

4. Platform as a service
Another SaaS variation, this form of cloud computing delivers development environments as a service. You build your own applications that run on the provider's infrastructure and are delivered to your users via the Internet from the provider's servers. Like Legos, these services are constrained by the vendor's design and capabilities, so you don't get complete freedom, but you do get predictability and pre-integration. Prime examples include Salesforce.com's Force.com, Coghead and the new Google App Engine. For extremely lightweight development, cloud-based mashup platforms abound, such as Yahoo Pipes or Dapper.net.

5. MSP (managed service providers)
One of the oldest forms of cloud computing, a managed service is basically an application exposed to IT rather than to end-users, such as a virus scanning service for e-mail or an application monitoring service (which Mercury, among others, provides). Managed security services delivered by SecureWorks, IBM, and Verizon fall into this category, as do such cloud-based anti-spam services as Postini, recently acquired by Google. Other offerings include desktop management services, such as those offered by CenterBeam or Everdream.

6. Service commerce platforms
A hybrid of SaaS and MSP, this cloud computing service offers a service hub that users interact with. They're most common in trading environments, such as expense management systems that allow users to order travel or secretarial services from a common platform that then coordinates the service delivery and pricing within the specifications set by the user. Think of it as an automated service bureau. Well-known examples include Rearden Commerce and Ariba.

7. Internet integration
The integration of cloud-based services is in its early days. OpSource, which mainly concerns itself with serving SaaS providers, recently introduced the OpSource Services Bus, which employs in-the-cloud integration technology from a little startup called Boomi. SaaS provider Workday recently acquired another player in this space, CapeClear, an ESB (enterprise service bus) provider that was edging toward b-to-b integration. Way ahead of its time, Grand Central -- which wanted to be a universal "bus in the cloud" to connect SaaS providers and provide integrated solutions to customers -- flamed out in 2005.

Another cloud computing resources:
  1. http://en.community.dell.com/blogs/cloudcomputing/default.aspx
  2. http://www.microsoft.com/presspass/press/2008/oct08/10-27PDCDay1PR.mspx
  3. http://www.microsoft.com/azure/default.mspx
  4. http://en.wikipedia.org/wiki/Cloud_computing
other resources can be found by searching with keyword "Cloud Computing"

Ini bukan gaya-gayaan sob, tapi ini adalah tren komputer ke depan, dimana kita harus bisa dan siap mengadopsinya.
Cheers, frizzy2008.

Network Security Appliances Overview

Fahmi Rizwansyah says:

Network Monitoring
The purpose of network monitoring is the collection of useful information from various parts of the network so that the network can be managed and controlled using the collected information. Most of the network devices are located in remote locations and they usually don't have directly connected terminals. Hence specialized tools are required to facilitate the network management application to monitor their status easily.

Bandwidth management
Heavy downloading can take its toll on network performance. Congestion and lack of responsiveness are often the result of large amounts of traffic being used by a small number of users. Sometimes even a single user can bring an entire network to a crawl as the internet gateway gets flooded with network traffic. By using Bandwidth management tools, the administrator can have full control over the network using tools to allocate desired bandwidth to specified users for specified tasks.

Traffic Analysis
Traffic analysis is the Inference or deduction of useful intelligence from patterns of observable characteristics of data flow(s), even when the data is encrypted or otherwise not directly available. The characteristics used for the evolution of such patterns include the identities and locations of the source(s) and destination(s), and the presence, amount, frequency, and duration of occurrence.

Penetration Testing
The portion of security testing in which the evaluators attempt to circumvent the security features of a system. The evaluators may be assumed to use all system design and implementation documentation, that may include listings of system source code, manuals, and circuit diagrams. The evaluators work under the same constraints applied to ordinary users. Ethical Hacking of a commissioned system is an integral part of penetration testing.

Vulnerability Analysis
Vulnerability analysis is the systematic examination of an AIS (Automated Information System for acquisition, storage, manipulation, control, display, transmission, or reception of data etc.) or product to determine the adequacy of security measures, identify security deficiencies, provide data from which to predict the effectiveness of proposed security measures, and confirm the adequacy of such measures after implementation.

Network audit
It is the process of assessing the various components and the operating environment of a computer network for vulnerabilities and other loopholes that might occur in the process of installing, configuring, or securing the network. This process may range from a relatively simple Automated audit to check a network for known vulnerabilities in the operating system through a black box or even a white box or manual audit to determine the network's overall status as compared to the prevailing "best practice".

Cheers, frizzy2008.

IP Address Location Check

Fahmi Rizwansyah says:

Have you ever wondered "what is my IP address"?
Or thought about IP block addresses that belong to a specific country?

Maybe you are Looking for IP Address Locations or simple try to find easy way and learn more about protocols and TCP IP?
Have you ever used a web-based IP address lookup tool to find the geographical location of an IP address?
Maybe you are looking for an IP address location or you simply wish to learn more about how networking protocols, like UDP and TCP/IP, work?
We can help with all of this and more.

Using IP Address Location is free. It is the fastest, easiest and most precise way to search and find the exact location of any IP address, OS, DNS, country, country code and contry flag. Furthermore, we have integrated Geolocator and a world map to display your results by city and country. Our IP database is updated every 48 hours so you can be sure the information we provide is up to date.

Our web based IP Lookup tool has analyzed your IP address and and detected next informations about your computer:
My IP Address
125.160.138.11

My Host Address (DNS Lookup)
11.subnet125-160-138.speedy.telkom.net.id
Proxy Server Detection:
No Proxy detected or you use High Anonymous Proxy

Country - Flag - Code Country
Indonesia ID

Guessed City
Jakarta

Language
English (United States)

Operating System
Windows
NT 5.1 (Windows XP)
Cheers, frizzy2008.

Straight-through UTP cables: Cabling tips for network professionals

Fahmi Rizwansyah says:

This part of our series will focus on the wiring of CAT5 cable because it is the most common type of UTP cable in the world. It's flexible, easy to install and very reliable when wired properly. We'll also cover wiring classic CAT1 phone cables. It is very important that you know exactly how to wire UTP cables. Cabling is the base of a solid network, and doing it correctly the first time will help you avoid hours of frustration and troubleshooting. On the other hand, if you are dealing with a poorly cabled network, this knowledge will help you to find the problem and fix it more efficiently.

Wiring UTP cables
We are now going to look at how UTP cables are wired. There are two popular wiring schemes that most people use today: the T-568A and T-568B. These differ only in which color-coded pairs are connected -- pairs 2 and 3 are reversed. Both work equally well, as long as you don't mix them. If you always use only one version, you're okay, but if you mix A and B in a cable run, you will get crossed pairs.


RJ-45 jack and plugUTP cables are terminated with standard connectors, jacks and punchdowns. The jack/plug is often referred to as a "RJ-45," but that is really a telephone company designation for the "modular eight-pin connector" terminated with the USOC pinout used for telephones. The male connector on the end of a patch cord is called a "plug" and the receptacle on the wall outlet is a "jack."
UTP color codes

As I've already mentioned, UTP has four twisted pairs of wires. The illustration shows the pairs and the color codes they have. As you can see, the four pairs are labeled. Pairs 2 and 3 are used for normal 10/100 Mbps networks, while pairs 1 and 4 are reserved. In Gigabit Ethernet, all four pairs are used.

The picture below shows the end of a CAT5 cable with an RJ-45 connector. These are used by all cables to connect to a hub or to your computer's network card. The picture below that shows a stripped CAT5 cable and identifies the four twisted pairs.


CAT5 cable with an RJ-45 connector stripped CAT5 cable








And don't think that UTP CAT5 cable only comes in one boring color -- those days are over! You'll find a wide range of choices today, as you can see below.
UTP CAT5 cable colors UTP CAT5 cable colors UTP CAT5 cable colors

T-568A and T-568B four-pair wiring
Ethernet is generally carried in eight conductor cables with eight-pin modular plugs and jacks. The connector standard is called "RJ-45" and is just like a standard RJ-11 modular telephone connector, except it is a bit wider to carry more pins.

Note: Keep in mind that the wiring schemes we are going to talk about are all for straight-through cables only.

The eight-conductor data cable contains four pairs of wires. Each pair consists of a solid colored wire and a white wire with a stripe of the same color. The pairs are twisted together. To maintain reliability on Ethernet, you should not untwist them any more than necessary (about 1 cm). The pairs designated for 10 and 100 Mbps Ethernet are orange and green. The other two pairs, brown and blue, can be used for a second Ethernet line or for phone connections.

There are two wiring standards for these cables, called "T568A" (also called "EIA") and "T568B" (also called "AT&T" and "258A"). They differ only in connection sequence -- that is, which color is on which pin, not in the definition of what electrical signal is on a particular color.

T-568A is supposed to be the standard for new installations, while T-568B is an acceptable alternative. However, most off-the-shelf data equipment and cables seem to be wired to T568B. T568B is also the AT&T standard. In fact, I have seen very few people using T568A to wire their network. It's important not to mix systems, as both you and your equipment will become hopelessly confused.
Pin number designations for T568B
Note that the odd pin numbers (1, 3, 5 and 7) are always the white with a stripe of color. The wires connect to RJ-45 eight-pin connectors as shown below:
568B wiring method Pin number designations for T568B

Here we break out the color codes for T568B:

Pin 1: white/orange (pair 2) TxData +
Pin 2: orange (pair 2) TxData -
Pin 3: white/green (pair 3) RecvData+
Pin 4: blue (pair 1)
Pin 5: white/blue (pair 1)
Pin 6: green (pair 3) RecvData-
Pin 7: white/brown (pair 4)
Pin 8: brown (pair 4)

The wall jack may be wired in a different sequence, because the wires are often crossed inside the jack. The jack should either come with a wiring diagram or at least designate pin numbers. Note that the blue pair is on the center pins; this pair translates to the red/green pair for ordinary telephone lines which are also in the centre pair of an RJ-11 (green=white/blue, red=blue).
Pin number designations for T568A
The T568A specification reverses the orange and green connections so that pairs 1 and 2 are on the center 4 pins, which makes it more compatible with the telephone company voice connections. (Note that in the RJ-11 plug at the top, pairs 1 and 2 are on the center 4 pins.) The illustrations show the order of colors in T568A.
568A wiring method Pin number designations for T568A

Pin color codes for T568A in writing are as follows:

Pin 1: white/green (pair 3) RecvData+
Pin 2: green (pair 3) RecvData-
Pin 3: white/orange (pair 2) TxData +
Pin 4: blue (pair 1)
Pin 5: white/blue (pair 1)
Pin 6: orange (pair 2) TxData -
Pin 7: white/brown (pair 4)
Pin 8: brown (pair 4)

The diagram below shows the 568A and 568B in comparison:


568A vs 568B pinouts
Where are they used?
The most common application for a straight-through cable is a connection between a PC and a hub or switch. In this case, the PC is connected directly to the hub or switch, which will automatically cross over the cable internally, using special circuits. In the case of a CAT1 cable, which is usually found in telephone lines, only two wires are used. These do not require any special cross over since the phones connect directly to the phone socket.


CAT5 straight-through cable connecting PC to hub

The picture above shows a standard CAT5 straight-through cable used to connect a PC to a hub. You might expect the TX+ of one side to connect to the TX+ of the other side, but this is not the case. When you connect a PC to a hub, the hub will automatically x-over the cable by using its internal circuits. The result is that pin 1 from the PC (which is TX+) connects to pin 1 of the hub (which connects to RX+).This happens for the rest of the pinouts as well.

If the hub didn't cross over the pinouts using its internal circuits (this happens when you use the uplink port on the hub), then pin 1 from the PC (which is TX+) would connect to pin 1 of the hub (which would be TX+ in this case). So, no matter what we do with the hub port (uplink or normal), the signals assigned to the eight pins on the PC side of things will always remain the same. The hub's pinouts, however, will change depending whether the port is set to normal or uplink.