How Cloud Computing can make a small company look big

Using Cloud Computing can make you company look larger than what it really is. If a small company wants to have a website they can. There are many different companies that will host your website and if you need them to design it they will do that also. It is also nice to have your domain and email address match. This allows a company in a small town to reach all over the world for a small cost. The company can have a toll free fax line for less than a basic phone line.  With this fax line you can send faxes from your computer or receive faxes to you email or check it on the internet. With this fax system you can check your faxes as long as you have access to the internet or check you email.  You can also have your faxes sent to more than one email address. Most companies use a Post Office Box that does not tell you the size of the company.

When a small business is just starting out, they want to look bigger that what they are. These are just a few things that they can do to reach more people and look larger than what they are for a small coast. When a company large or small looks professional customers feel secure about doing business with that company.

RIPv2 vs EIGRP

RIPv2 improves upon RIPv1 with the ability to use VLSM, with support for route authentication, and with multicasting of route updates. RIPv2 supports CIDR. It still sends updates every 30 seconds and retains the 15-hop limit; it also uses triggered updates. RIPv2 still uses UDP port 520; the RIP process is responsible for checking the version number. It retains the loop-prevention strategies of poison reverse and counting to infinity. On Cisco routers, RIPv2 has the same administrative distance as RIPv1, which are 120. Finally, RIPv2 uses the IP address 224.0.0.9 when multicasting route updates to other RIP routers. As in RIPv1, RIPv2 will, by default, summarize IP networks at network boundaries. You can disable auto summarization if required.

 EIGRP in the early 1990s as an evolution of IGRP toward a more scalable routing protocol for large internetworks. EIGRP is a classless protocol that permits the use of VLSMs and that supports CIDR for the scalable allocation of IP addresses. EIGRP does not send routing updates periodically, as does IGRP. EIGRP allows for authentication with simple passwords or with MD5. EIGRP auto summarizes networks at network borders and can load-balance over unequal–cost paths. Packets using EIGRP use IP protocol 88. Only Cisco routers can use EIGRP.

EIGRP is an advanced distance-vector protocol that implements some characteristics similar to those of link-state protocols. Some Cisco documentation refers to EIGRP as a hybrid protocol. EIGRP advertises its routing table to its neighbors as distance-vector protocols do, but it uses hellos and forms neighbor relationships as link-state protocols do. EIGRP sends partial updates when a metric or the topology changes on the network. It does not send full routing-table updates in periodic fashion as do distance-vector protocols. EIGRP uses DUAL to determine loop-free paths to destinations. This section discusses DUAL.

Remember RIPv2 is for small network and EIGRP is for large networks.  RIPv2 update every 30 sec and EIGRP only update when there is a change saving on bandwidth

Layer 3 protocols (Network Layer)

IS-IS-Intermediate System-to Intermediate System is a routing protocol designed to move information efficiently within a computer network, a group of physically connected computers or similar devices. It accomplishes this by determining the best route for datagrams through a packet-switched network. The protocol was defined in ISO/IEC 10589:2002 as an international standard within the internet standard (OSI) reference design.

OSPF- Open Shortest Path First is an adaptive routing protocol for internet protocol (IP) networks. It uses a link state routing algorithm and falls into the group of interior routing protocols, operating within a single autonomous system (AS). It is defined as OSPF Version 2 in  for Ipv4. There is an  updates for Ipv6 that is specified as OSPF Version 3

BGP- Border Gateway Protocol is the protocol backing the core routing decisions on the internet. It maintains a table of IP networks or 'prefixes' which designate network reach ability among autonomous systems

RIPv1 Routing  Information Protocol is a dynamic routing protocol  used in local and wide area networks

Easy Subneting

128      64        32        16        8          4          2          1

To calculate the number of hosts or the number of networks for a given subnet mask, use the following formula:

2^(number of bits used) - 2 = number of networks/hosts (The ‘^’ means ‘raised to the power of’.)

So, given the fact that we have borrowed 2 bits to extend our network, we have 2^2 - 2 = 2 networks (remember, we are excluding the all 1 and all 0 networks).

We have 14 bits left to describe the hosts on each network; therefore we have 2^14 - 2 = 16,382 hosts per network (remember we are excluding host addresses with all 0s or all 1s).

The value of the lowest order bit in the subnet mask tells you two things: a) it tells you the first network ID for the subnets created by the extended subnet mask, b) it tells you the value that you can add to one network ID to arrive at the next possible network ID.

Let’s take our example extended subnet mask of 255.255.192.0. The 3rd octet expressed in binary with the decimal equivalents is:

128 64 32 16 8 4 2 1

1 1 0 0 0 0 0 0

The value of the lowest order bit is 64. Therefore, our first network ID is 172.16.64.0/18. The next and last network ID is 172.16.128.0/18 (64 + 64 = 128)

VLAN

By default, all switches are configured to be VTP servers. This configuration is suitable for small-scale networks in which the size of the VLAN information is small and the information is easily stored in all switches (in NVRAM). In a large network, the network administrator must make a judgment call at some point, when the NVRAM storage that is necessary is wasteful because it is duplicated on every switch. At this point, the network administrator must choose a few well-equipped switches and keep them as VTP servers. Everything else that participates in VTP can be turned into a client. The number of VTP servers should be chosen in order to provide the degree of redundancy that is desired in the network.

VLAN is a software concept, identifiers and configurations for a VLAN must be properly prepared for it to function as expected. Frame coloring is the process used to ensure that VLAN members or groups are properly identified and handled. With frame coloring, packets are given the proper VLAN ID at their origin so that they may be properly processed as they pass through the network. The VLAN ID is then used to enable switching and routing engines to make the appropriate decisions as defined in the VLAN configuration.If the VLAN is not properly configured that part of the network will be down.

RIPv1 vs RIPv2

The main difference between RIPv1 and RIPv2 is classless routing. RIPv2 incorporates the addition of the network mask in the update to allow classless routing advertisements. This is extremely important for the flexibility needed to efficiently utilize network assignments for an ever-shrinking pool of IP addresses.

There are other differences, as well. In RIPv2, the destination address for the updates is multicast, instead of broadcast, as in RIPv1. This reduces the burden on the network devices that do not need to listen to RIP updates. With broadcast, every device on the broadcast domain must at least open the IP packet and process the initial information to determine relevance. With multicast addressing, if a device needs that information, it will listen to that specific address. If it does not need the RIP information, it does not have to process the multicast address. The multicast address RIPv2 sends to is 224.0.0.9.

NAT

With the explosion of the Internet and the increase in home networks and business networks, the number of available IP addresses is simply not enough. The obvious solution is to redesign the address format to allow for more possible addresses. This is being developed (called IPv6), but will take several years to implement because it requires modification of the entire infrastructure of the Internet.

­ This is where NAT comes to the rescue. Network Address Translation allows a single device, such as a router, to act as an agent between the Internet ( "public network") and a local (or "private") network. This means that only a single, unique IP address is required to represent an entire group of computers.

NAT also blocks your private network from the world.

Be ready to your Cisco test

Select the path that best fits your experience and career goals. Paths include routers, service providers and field technicians. General and specialist tracks are available to fit anyone.Identify the certification level consistent with your current position.

Associate certification is the beginner level designed for new hires. Professional is the second level offered and is targeted to journeymen and middle managers with access to more specialized certifications. Specialist certification provides expert level exams with deeper security knowledge.

Study the exam requirements at Cisco's website under "Training and Events" to verify a good fit with experience and knowledge. Assessment tests are a good way to ensure success before registration. Professional and specialist exams require considerable expertise, preparation classes are often required prior to registration.

Go over all training and exam material carefully. Start a study group to assist in going over material that may be difficult or outside your normal range of knowledge. This also offers a great chance to network with other people in the industry
Arrive at your test location 15 minutes prior to test time. Bring two forms of ID along with scratch paper and pen. Tests vary in length depending on the course of study.

How to get CCNS certified

dfd

Frame Relay

The Frame Relay frames are transmitted to the destination by virtual circuits to the destination point. Virtual circuits may be permanent (PVCs) or switched (SVCs). PVCs are set up administratively by the network manager for a dedicated point-to-point connection; SVCs are set up on a call-by-call basis.

Frame Relay offers an alternative to both dedicated lines and X.25 networks for connecting LANs to switches and routers. The success of the Frame Relay protocol is based on the following two underlying factors:

Because virtual circuits consume bandwidth only when they transport data; many virtual circuits can exist simultaneously across a given transmission line. Also each device can use as much of the bandwidth as necessary, and can operate at higher speeds.

The improved reliability of communication lines and increased error-handling sophistication at end stations allows the Frame Relay protocol to discard erroneous frames and eliminate time consuming error handling processing.

These two factors make Frame Relay a desirable choice for data transmission; however, they also necessitate testing to determine that the system works properly and that data is not lost

ATM (Asynchronous Transfer Mode)

Asynchronous Transfer mode (ATM) is a high speed network that support voice and data communications. ATM operates on data link layer (Layer 2 in the OSI model); it runs over fiber or twisted pair copper cable.

ATM differs from more common data link technologies like Ethernet in several ways.  ATM does not use routing protocols. Hardware devices known as ATM switches establish point-to-point connections between the sources and destination. ATM does not use variable length packets, it uses fixed sized cells. ATM cells are made up of 48 bytes of data and 5 bytes for the header information totaling 53 bytes.

ATM technology is designed to improve utilization and quality of service (QoS) on high-traffic networks. Without routing and with fixed-size cells, networks can better manage bandwidth under ATM than under Ethernet. Because of the high cost of ATM compared to Ethernet, ATM is used for the backbone and other high performance, specialized networks.

ATM is designed to be easily implemented by hardware and, faster processing and switch speeds are possible. The bit rates are either 155.520 Mbps or 622.080 Mbps. Speeds on ATM networks can reach 10 Gbps. Along with Synchronous Optical Network (SONET) and several other technologies, ATM is a key component of broadband ISDN (BISDN).

How does DNS work

Domain Name System (DNS) is a database system that translates a computer’s fully qualified domain name into an IP address. Network computer use IP address to locate and connect to computers.  What DNS servers do is it converts a user friendly name like Yahoo.com to a numeric IP address of 209.191.122.70. It is easier to for humans to remember the domain name that the IP address. Reverse DNS (rDNS) does just the opposite of DNS; it takes the IP address and converter it to friendly user names.

Any organization that maintains a computer network will have at least one Name server that handles the DNS queries. The name server holds a list of all IP address within the network, along with cache of IP address from other domain names. When a computer requests an IP address there is three things that can happen.

1.      If the request is a local IP address then the request goes to the Name server that is configured on you work station. Your response will be quickly almost instantly.

2.      If the request is not one of the local address, but someone in the network has requested the information recently. The request will be for filled from the cache on the name server. Then you will receive you information will be a quit response.

3.      If the request is not a local IP address, and no one has requested the IP address. The name server will perform a search on behalf of the workstation this search may involve querying two or more other name servers at are at remote locations. These queries can take anywhere from a second or two up to a minutes.

If you are trying to get to a website and you keep getting an error message your DNS may have old data. The website may have had changes and the cache in your DNS server needs to be cleared. It is import to clear the cash in the name server for this reason.

iPad 2 for High School students

The iPad2 is 33% thinner and 15% lighter than the old iPad the old iPad weight is 1.5 pounds How could this work in the school system in helping it to become greener, cut the coast of text book, and lighten the back packs of the students.

The text books could be viewed on line as a PDF file. This will also eliminate the excurse of that the students saying that they forgot their books. The student would not have to keep up with multiple text books. The children would also be able to keep their notes on the iPad. The teachers would be able to send the students their assignments and notes electronically. This will eliminate a lot of paper. If the student needs to have meeting with the student with the iPad2 they would be able to do a web conference. The iPad has two cameras that will allow you to talk and see the person at the same time.

The coast of the iPad starting coast is $499.00 and by buying in bulk you will get a discounst also with any software that you will need for the students. The coast could be spread over four years along with insurance that would cover in the event of it being lost or damaged. The coast of school books are about $30-$40 per book. Once the books are printed there is no changing. When the books become outdated then you will have to print more. By viewing it online in a PDF file keeping the student in current books would be cheaper.