This was a message/invitation received from a friend of mine regarding the upcoming Cisco Expo 2010 event in Athens Greece. For people that happen to be in the area, it would be a fantastic event with four excellent demos as described below:

Four demos, which encapsulate the innovation of Cisco will have the opportunity to watch the visitors of Cisco Expo 2010.

The great celebration of innovation will be held on Tuesday and Wednesday, April 20-21, 2010.

• The Cisco TelePresence, Cisco’s leading solution that offers the experience of face-to-face communications and removes their geographical constraints on cooperation, will be available to all visitors of the Cisco Expo. Two demo-rooms will be located in the exhibition space and communicate with each another in real-time.

• A commercial retail space, equipped with all modern technology that can make businesses more competitive, will be set up in the exhibition space. The Cisco Expo visitors will have the opportunity to experience wireless networking, unified communications and digital signage combined into one comprehensive solution for commercial stores of the future.

• The Cisco EnergyWise, innovative solution for the management of energy in buildings and offices, will be presented on stage at an impressive demo simulating the workplace. The presentation is scheduled on Wednesday, April 21, at 15: 00, presented by Antonis Tsimpoykis, Cisco Borderless Architecture Leader, Med Region, with the collaboration of other skilled people from Cisco, which would come to Athens ’ only for this purpose.

• Cisco Expo Athens will also establish a unique demo in Digital Media for telecommunications service providers, which will be available both days of the event.

The Athens Cisco Expo 2010 will be held on 20 and 21 April 2010 in “THEATRON” – Greek World Culture Center, pireos254, in Athens.

Participation is free for all professionals in the information technology and telecommunications sectors. For registrations, you can visit the homepage www.ciscoexpo.gr

Hello there, this is Harris Andrea. Today I have redirected my older blog Cisco-Tips.com to its new domain home which is the website you are viewing now (NetworksTraining.com). Please update your bookmarks accordingly. I have configured a permanent 301 domain redirect (using .htaccess file) for the whole cisco-tips.com website and I have moved the old database to a new one which is used by a fresh WordPress installation on the new domain. This means that every single page of my old site will be redirected to its corresponding page on the new domain. All content from the older domain will be preserved. If you click on a link in Google search results with domain www.cisco-tips.com/xyz, this will be redirected automatically to www.networkstraining.com/xyz.

OK, many of you might be wondering why I decided to change the domain name of a site which was embraced by so many professionals. Well, it has to do with trademark issues with Cisco. After reading a post from Jeremy Cioara at ciscoblog.com (read post here), he is forced by Cisco to close down his existing blog because the domain name includes the Trademarked name “Cisco” in it. Before receiving any letters from Cisco lawyers, I decided to move away from cisco-tips.com and get a more generic domain name. I Don’t want to face any legal issues with Cisco. Before calling me a coward, let me tell you that by violating Cisco’s Trademark policy, you are also violating their certification NDA agreement. I wouldn’t want to risk my certification status for a domain name right?

Well, the only thing that I promise you is that I will continue to update this new blog with fresh content related to IP Networking with focus on Cisco technologies. So keep visiting often !!

The ASR 9000 has 6 times more capacity and is 4 times faster than any other router in the same category. It is able to transmit data at a rate of 6.4 terabits per second. What does this mean? It means that it is capable of transmitting 200 dvd video / sec or 250.000 mp3s / sec or 500.000 e-books / second. Therefore, the bandwidth capacity of the ASR 9000 router is 10 times of the Cisco ASR 1000. For example, the ASR 9000 supports 100 megabits per second (Mbps) to homes, compared to common legacy E1 or T1 connections which used to have around 1.5 to 2 Mbps.

«We really believe that the IP (Internet Protocol) traffic on the Internet will be growing by 46% annually up to 2012 while the bulk of traffic, about 90%, will be consumed by video,” said Pankaj Patel, senior vice president who manages the company’s relationships with telecommunications carriers.

The ASR 9000 has innovative technology for proactive management of video signals which are particularly difficult. It can repair and offer an excellent image quality and performance for HDTV and other video services, state executives of Cisco. It is ideal for companies such as AT & T and Verizon because they offer more and faster Internet video to mobile phones and for the PC consumers.

As a corollary, the company adds that the ASR 9000 operates 40% more effectively than other competing products, helping to save the planet and saving money for the network operators.

So far, some of the largest telecommunications companies in the world, including Softbank Corp. Japan have signed for the acquisition of such devices. The ASR 9000 router is using the same operating system as the Cisco CRS – 1 that transmits data with rate of 92 trillion bits per second and which now ‘runs’ for more than 200 telecommunication operators in the high speed lanes of the world wide web. When the Cisco launched CRS-1 in 2004, some analysts said that these heavy duty network machines (weighing 2,300 pounds and having a height of 7 feet) did not satisfied customers’ wishes. They even predicted that the San Jose company will not sell more than 50 units. Pankaj however stated that Cisco now sells at least 50 such routers per week. Last year, the company earned 39 billion U.S. dollars just from the sales of ASR routers.

Glen Hunt, an analyst at Current Analysis said that Cisco’s new router will cost providers at least $ 80,000. The ASR 9000 can be installed close to homes and business premises of consumers. This model took 4 years to get out to production and had cost $200 million U.S. dollars. According to Ray Mota, director of sales strategy of Synergy Research Group, the ASR 9000 will fill a gap in the production chain of Cisco and will help the San Jose company to maintain its market share. Cisco competes with companies like Alcatel – Lucent and Juniper Networks in the sales of routers. However, Cisco controls 59% of the market compared with Alcatel – Lucent controlling 15% and 14% for Juniper.

DHCP, as we all know, is a broadcast protocol (shame on you if you don’t know that already !!) which normally works only on the same Layer 2 broadcast domain. Does this mean that you need to have your DHCP Server connected to the same network subnet as the DHCP clients? If this was the case it would not be flexible or economical at all. What if you have segmented your internal network into many different subnets and you have DHCP clients in all those subnets. Would this mean that you must have a DHCP server for every subnet? Fortunately, you don’t need to have this situation. With the Cisco “ip helper-address” command configured on the Layer3 interface which receives the client’s DHCP broadcast, you can transform the broadcast request into a unicast and send it to a centralized DHCP server which can be located to a different subnet in your network. The unicast DHCP request will be routed normally to the destination DHCP Server within the network, even if the server is far away from the DHCP client.

The DHCP server must have an appropriate IP Pool scope configured for the specific subnet from where the DHCP request came. Using this IP scope, the server will assign an appropriate IP address to the requesting client. For example, if the DHCP client subnet is 192.168.1.0/24, then the remote DHCP server must have an IP Pool configured to assign addresses within the range 192.168.1.0/24. The source DHCP client subnet is determined by the IP address assigned to the Layer3 interface which has the ip helper-address configured.

Let’s see an example scenario below with a configuration snapshot.

From the network diagram above, two DHCP client PCs are located behind Router A. Interface Fe0/0 of the router has IP address 192.168.1.1/24. The DHCP clients will start broadcasting DHCP requests in order to get their IP address information assigned from a server. By default, these DHCP broadcast requests will be confined within Switch A and will never reach any other subnet beyond Router A. By configuring an “ip helper-address 10.10.10.1” under interface Fe0/0 of Router A, we tell the router to turn the DHCP broadcast into a DHCP unicast and send it to destination DHCP server 10.10.10.1. The server will see that the DHCP request came from source subnet 192.168.1.0/24 and will therefore assign an appropriate IP address from a configured IP pool scope within the range 192.168.1.0.

Configuration on Router A

RouterA# conf t
RouterA(config)# interface fastethernet0/0
RouterA(config-if)# ip address 192.168.1.1 255.255.255.0
RouterA(config-if)# ip helper-address 10.10.10.1

Some other important considerations for ip helper-address

By default, the ip helper-address command forwards also some other broadcast protocols in addition to the DHCP (BOOTP) protocol. It forwards by default the following eight UDP broadcast protocols:

• UDP 37 (Time protocol)
• UDP 49 (TACACS)
• UDP 53 (DNS)
• UDP 67 (DHCP Server)
• UDP 68 (DHCP Client)
• UDP 69 (TFTP)
• UDP 137 (NetBios)
• UDP 138 (NetBios Datagram service)

If you want to add more broadcast protocols to be forwarded, or even remove some of the default forwarded protocols, you can use the “ip forward-protocol” command under global config mode.

Example: Remove the NetBios protocols (137,138) from being forwarded by default, and add NTP protocol 123 to be forwarded by ip helper-address.

RouterA(config)# no ip forward-protocol udp 137
RouterA(config)# no ip forward-protocol udp 138
RouterA(config)# ip forward-protocol udp 123