Network Administration

By Raul Bernardino

Introduction:

Nowadays, the complex global communications over the networks are need better tools to monitor and manage them properly without a longer down time. This global networks complexity, we can analog them as a simple control room in any hotels for instance. Where in this control room can able monitor all movements around the hotel and inside hotel building. The tools for monitoring the movement can be used the CCTV, wire alarm control, anti theft alarm, general air conditioner control and etc. The control monitors are helping the in-charge persons or on duty officers to determine where the location of the defects or the troubles are coming from. It asked an immediate action and followed guidance and steps that are been agreed and written in the procedures in which is to minimize the impacts.  Rather than has to wait until it becomes wider occurred impacts, in which it will be probably took more energy and time to solve them.

With this similar situation above is also applied to the network administration. We should manage, control and monitor the deployment and maintenance of the hardware, software and connection or data communication link over the networks.

According to Saydam (1996), "Network management includes the deployment, integration and coordination of the hardware, software, and human elements to monitor, test, poll, configure, analyze, evaluate, and control the network and element resources to meet the real-time, operational performance, and Quality of Service requirements at a reasonable cost."

Even it is a simple network such as it is consisting of several routers, hosts and servers; we do still need to manage this network with a proper network management tools. This is can help the network administrators. Several tools of the network management that network administrator can use as follows:

• The interface failure detection at router or host or server: The appropriate network management tools, the network administrator may get report that one of the interface down. It is good detecting issue ahead and replaced that interface before it gets fail.
• The host monitoring: This can helps the network administrator to monitor all hosts in the network periodically.
• The traffic monitoring: This can helps the network administrator to monitor all the communication traffics over the network periodically and it is enable network administrator to drop unnecessary traffics (down-loader) or packages over the network as it needed.
• The rapid detection on routing table changes: This tool can help the network administrator to monitor the instability of the routing tables.
• The SLA Monitor: The service level agreement is a contract that both sides have agreed and the network administrator is based on whereas to monitor and to measure the performance of the service provider within the metrics.
• The intrusion detection: This tool can help the network administrator in which to monitor the strange traffic packages over routers or over networks.

There are five area of network management model that international organization for standardization defines as follows:

1. Performance Management: The performance management is to measure and to maximize the utilization of the devices and services within network.
2. Fault Management: The fault management is detecting and logs the issue including responding the fault condition of the network.
3. Configuration Management: The configuration management is allowing the network administrator to track down and monitor all configurations of the devices and it is including the hardware and software.
4. Accounting Management: The accounting management is allowing the network administrator to give the accesses to the users, logs the accesses of the resources over the network. The usages of the network resources are depending on the privileges.
5.  Security Management: The security management is controlling all the accesses base on the policies and procedures.

The network management infrastructure is managing the devices in which contain of the objects of data (entities).  Managing the network infrastructure as it shows in the below diagram:

In conclusion:

The network management is important in today’s global networks complexity. The network management tools is helping to minimize the downtime or increasing the reliability of the networks whereas it is also can be accessible from anywhere at any time.

References list:

1.     Kurose, J.F. & Ross, K.W. (2010) Computer Networking: A Top-Down Approach. 5^th ed. Boston: Addison Wesley

2.     University of Liverpool/Laureate Online Education (2011) Lecture notes from Computer Networking Module Seminar 8 [Online]. Available from: University of Liverpool/Laureate Online Education VLE (Accessed: 24 September 2011)

File Sharing

By Raul Bernardino

Introduction:

The implementation of Peer to Peer (P2P) system is often seeing as an abstract of the overlay network. The P2P application is distributing information in the computing or networking between Head Quarter (HQ) and branches offices (Close Networks) and anonymity (Open Network).

The close networks usually use intranet to distribute information among the company or the institution, including the file sharing. They use peer to peer technology to share their information by sub-netting Internet Protocol (IP).

The World Bank Group institution uses P2P technology to share information among country offices around the world. The HQ based in the Washington DC has to communicate with the rest of the offices in about 184 countries. This is the larger institution in the world. They are sharing their information and knowledge across the countries and regions, including the best practice from country to country. The sharing knowledge has based on team information and it has become huge knowledge (documents management) and it is later becomes a knowledge library. Moreover, the sharing information enable team in the fields (country based) will work more effective and efficient. Especial World Bank Group adopts matrix structure in their daily operations. Additional, to enabling the sharing the information across the globe, to be reliable, effective and efficient, the World Bank Group invests a lot of capital in the information and technology sector every year.

The United Nations institution is the second larger institution that operates in the conflict countries. They are also using a close network to disseminate information among HQ in New York and with mission operation units in the conflict or post conflict countries. Usually, the establishment of the United Nation (UN) mission in any request country has to have a good established communication in order to have an effective communication back to the HQ. For instance, in Timor-Leste, the last UN mission was United Nations Integrated Mission in Timor-Leste has direct communication with HQ by using P2P VSAT communication system. This sharing information is closed to the public.

The motivation of having the anonymity in the P2P networks are user desired. The users do not want their identities are published. The other common reasons as follows:

• The distribution of the materials are illegal
• Legal material such alcohol, people or organization intend to be anonymity
• Fear of retribution because unofficial leaks
• Censorship at local, national level, and organization
• Privacy to avoid tracking and data mining

Other companies that use P2P are:

Bittorrent: The BitTorrent Company is Software Company based in San Francisco who uses P2P to distribute for downloading. It has several features such as discovery, speedy, advance, plug and play, simple, customizable, intelligent, and reliable. I personally not test this features yet.

Pondo: Pondo is may represent future distribution media. Pondo has “solved the larger file attachment problems”, the wall street Journal Said.

SubEthaEdit: It is shared editor to allow the developers to work as the team from the different location. This is very handy tools for programmers who are developing a complex program and need a team to write a code.

Limewire: The limewire company currently registered in the court dated on October 26^th, 2010 to stop the limewire software distribution.

Microsoft: The Company uses Windows Server Update Services (WSUS) to distribute the updates to every register clients

Conclusion: The P2P communication becomes one of the available technologies to use for sharing and distributing information including updates among entities. It is also freely distributing unnecessary adware to the target clients in order to gain the information or attack with viruses.

References list:

1.     Peer to Peer, [on-line]. Available from: http://en.wikipedia.org/wiki/Peer-to-peer  (Accessed: 6 August 2011)

2.     Activities by country, [on-line]. Available from: http://web.worldbank.org/WBSITE/EXTERNAL/COUNTRIES/0,,pagePK:180619~theSitePK:136917,00.html (Accessed: 6 August 2011)

3.     UN Peace Peaking, [on-line]. Available from: http://www.unmissions.org/ (Accessed: 6 August 2011)

4.     Pondo, [on-line]. Available from:  http://www.pando.com/  (Accessed: 6 August 2011)

5.     BitTorrent: Downloading easy, [on-line]. Available from:  http://www.bittorrent.com/features (Accessed: 6 August 2011)

6.     Limewire, [on-line]. Available from:  http://www.limewire.com/ (Accessed: 6 August 2011)

7.     What Is Windows Server Update Services (WSUS)?, [on-line]. Available from:  http://www.wsuswiki.com/whatiswsus (Accessed: 6 August 2011)

Network Management Concept

By Raul Bernardino
Introduction:
Nowadays, the network management has become very complex issues; this is starting from a single host to a millions hosts round the globe. We simple just don’t know who they are in the globe networks. Therefore, it is important to treat network management as an integral part of the network infrastructure management. Moreover, it is to enable us in monitoring and controlling the traffics. It is also enable us in maintaining all resources such as hardware, software, system configuration, and etc.

The Management Information Base (MIB) is virtual storage information of the objects that transmits through the networks. As per 2006, there were more than 200 standards of the MIB modules. The Internet Engineering Task Force (IETF) is a group of individuals that care about internet quality, influence designers, and manage the internet. They (IETF) adopted these standards and standardized this object identification with framework of the Open System Interconnection (OSI). The OSI object identifier tree can be sees in the diagram below:

Q1a:  The ‘1.2.840.113549’ standards object identifier (OIDs) is for the RSADSI.  Where the ‘1’ is for ISO assigned OIDs, ‘1.2’ is for ISO member body, ‘1.2.840’ is for USA, and ‘1.2.840.113549 is for RSADSI.

Q1b: The new Microsoft file format product in the OIDs tree is ‘1.2.840.113556.4.x’. Where ‘1’ is for ISO assigned OIDs, ‘1.2’ is for ISO member body, ‘1.2.840’ is for USA, and ‘1.2.840.113556 is for Microsoft, ‘1.2.840.113556.4’ is for Microsoft file format, and ‘1.2.840.113556.4.x’ is for new product of Microsoft file format.

Q2: The SNMP stands for Simple Network Management Protocol. The message types and functions over the SNMP protocol as it shows in the table below:

The big differences of the trap and request respond messages in SNMP as follows:

-         The trap message: the SNMP agent sent message to the SNMP manager and it is not requiring any responds from the SNMP manager, and it is including sent inform request and respond; as it shows in figure 1, 2 and diagram below:

 Figure 1 Trap Sent to SNMP Manager Successfully

 Figure 2 Inform Request Sent to SNMP Manager Successfully

However, if it is unsuccessful during trap message sent, the SNMP agent does not know the trap has reached the destination and the SNMP manager also does not receive any inform request as it shows in figure 3 below:

The agent sent several inform request from SNMP agent to the SNMP manger on the trap model until it reaches the SNMP manger; as it shows in figure 4 below:

-         While the request and the response messages are sent by the agent to manager entity, with the response coming back from the manager entity; as it shows in diagram below:

Q3: The Internet has no presentation layer. Additionally, in the table of the TCP/IP layer in which has four layers according to the IETF were defined in RFC 1122:

We can compare the TCP/IP layer with 7 OSI layers as in diagram below:

The application layer in the TCP/IP is representing application, presentation, and session layers in the OSI layer. While internet layer in the TCP/IP represents network and data-link layer in the 7 OSI layers. Other literatures especially bottom up approach split link layer in to two layers such physical and data-link layer then TCP/IP layer become five layers.  

Moreover, network topology diagram below is illustrated two Internet host computers are communicating through the local network boundaries comprised with the routers.

 The SNMP engine and application will be taking care of the differences of the machine architecture, data format, message processing, and it is including the security of data communication over the network. As it shows in diagram below:

Furthermore, the message format over Protocol data Unit (PDU) as it shows in diagram below:

Q4: Before I am going to answer the question, I have to elaborate the ASN.1. The ASN.1 stands for Abstract Syntax Notation 1 which is the ISO’s that used numbers in the internet protocol, especially in the network management. The question was how each of computers can read those transmitted data from different architecture and program as it shows in diagram below:

The issue is on data formats and storage conventions. Potential solutions as follows:

a)     The senders are learning format from the receivers.  In the real world analogy may not apply. There is still pro and cons.

b)    The receivers are learning the sender’s format. In the reality this can be a real world analogy however there is still pro and cons.

c)     Senders and receivers are translate independently each own format. It is not fitted with real world analogy.

The scenario above can be illustrated  in a diagram below:

In order to solve situation above:

1.     Translate local host format in to independent host format

2.     Translate data in to independent host format

3.     Translate independent host format to the remote host format

 As it shows in diagram below:

The ASN.1 provides several things such as:

1.     In the ISO standard X.680 is used extensively in the internet

2.     To define data type and object constructor like SMI (Structure of Management Information)

3.     BER stands for Basic Encoding Rule in which the ASN.1 will define data object to transmit. Where each transmission of the object has a type, length, and value (TLV) encoding.

The TLV has tag value and type as follows:

Tag Value   Type                              Description

1                 BOOLEAN                    Value is true or false

2                 INTEGER                      Can be arbitrary large

3                 BITSTRING                  List of one or more bits

4                 OCTET STRING                    List of one or more bytes

5                 NULL                            No value

6                 OBJECT IDENTFIER   Name, in ASN.1 standard naming tree

9                 REAL                            Floating point

Example of the BER in the TLV encoding for character string “Smith” with value 259 as it can be illustrated in a diagram below:

The answer for strings “greg” and value 277. The binary for the decimal of 277 is 00000001 00010101. The first binary value is 1 and followed by value of the byte is 21. The first byte of the stream value is 4 in which indicating type of data is OCTET STRING and the length of OCTET STRING is 4 (“greg”); followed by 2 integers (type of data and length of integer).  The result is ” 4 4 ‘g’ ‘r’ ‘e’ ‘g’ 2 2 1 21”, as it can be illustrated in a diagram below:

Reference List:

1.     Kurose, J.F. & Ross, K.W. (2010) Computer Networking: A Top-Down Approach. 5^th ed. Boston: Addison Wesley

2.     University of Liverpool/Laureate Online Education (2011) Lecture notes from Computer Networking Module Seminar8 [Online]. Available from: University of Liverpool/Laureate Online Education VLE (Accessed: 21 September 2011).

3.     Cisco IOS Software Releases 11.3: SNMP Inform Requests, [Online]. Available from: http://www.cisco.com/en/US/docs/ios/11_3/feature/guide/snmpinfm.html (Accessed: 27 September 2011)

4.     The deference between TCP/IP and OSI layer, [Online]. Available from:  http://forums.techarena.in/technology-internet/1113879.htm (Accessed: 27 September 2011)

5.     Network Management Review question, [Online]. Available from:  http://subjects.ee.unsw.edu.au/tele4354/downloads/revCh9.pdf (Accessed: 27 September 2011)

6.     RSA data security Inc, [Online]. Available from:  http://www.alvestrand.no/objectid/1.2.840.113549.html  (Accessed: 27 September 2011)

7.     Wikipedia (N), OSI model, [Online]. Available from:  http://en.wikipedia.org/wiki/OSI_model (Accessed:  30 September 2013)

8.     Website (N), The internet engineering Task Force, [Online]. Available from: http://www.ietf.org/(Accessed:  30 September 2013)

9.     Wikipedia (N), Protocol Data Unit, [Online]. Available from: http://en.wikipedia.org/wiki/Protocol_data_unit (Accessed:  30 September 2013)