VAMs can perform a variety of network
functions, including splitting, multi-
plexing, and providing access within
fiber networks, the most popular appli-
cation today is non-intrusive monitor-
ing, which lets providers proactively
troubleshoot their networks without
forcing a disruption of service on cus-
As businesses become increasingly dependent on the
network, the availability of the network infrastructure
becomes a critical business concern.
• Redundancy is the solution for achieving the necessary
• Layer 2 redundancy improves the availability of the
network by implementing alternate network paths by
adding equipment and cabling.
• Having multiple paths for data to traverse the network
allows for a single path to be disrupted without impacting
the connectivity of devices on the network...
In this chapter, you learned to: Describe the structure of a network, including the devices and media that are necessary for successful communications; explain the function of protocols in network communications; explain the advantages of using a layered model to describe network functionality;... Inviting you to refer.
Learning objectives of this chapter include: Explain the structure IP addressing and demonstrate the ability to convert between 8-bit binary and decimal numbers, given an IPv4 address, classify by type and describe how it is used in the network, explain how addresses are assigned to networks by ISPs and within networks by administrators,...
Describe the structure of a network, including the devices and media that are necessary for successful communications. Explain the function of protocols in network communications. Explain the advantages of using a layered model to describe network functionality. Describe the role of each layer in two recognized network models: The TCP/IP model and the OSI model. Describe the importance of addressing and naming schemes in network communications.
This publication was developed to assist professionals preparing for Cisco Certified Internetwork
Expert (CCIE) candidacy, though it is a valuable resource for all internetworking professionals. It is
designed for use in conjunction with other Cisco manuals or as a standalone reference. You may find
it helpful to refer to the Cisco CCIE Fundamentals: Case Studies, which provides case studies and
examples of the network design strategies described in this book.
Wireless Sensor Networks (WSNs) can be defined as a self-configured and infrastructure-less wireless networks to monitor physical or environmental conditions, such as
temperature, sound, vibration, pressure, motion or pollutants and to cooperatively pass
their data through the network to a main location or sink where the data can be observed
and analysed. A sink or base station acts likean interface between users and the network.
One can retrieve required information from the network by injecting queries and gathering
results from the sink.
The requirements for a network administrator have always been diverse. Get the users connected, make sure there’s enough bandwidth to run applications, keep the network secure, and so on.
When problems come up on a traditional network, the solutions have often been fairly straightforward. If users aren’t connected, you connect them. If there’s not enough bandwidth, you buy new equipment. If network resources are vulnerable, you introduce appliances and applications that provide enhanced security. It’s a pretty
tight loop of problems and solutions....
The growth in the use of mobile networks has come mainly with the third generation
systems and voice traffic. Withthe current third generation and the arrival of the 4G, the
number of mobile users in the world will exceed the number of landlines users. Audio
and video streaming have had a significant increase, parallel to the requirements of
bandwidth and quality of service demanded by those applications. Mobile networks
require that the applications and protocols that have worked successfully in fixed
networks can be used with the same level of quality in mobile scenarios.
For campus networks, Cisco recommends a hierarchical network design that distributes networking
function at each layer through a layered organization. The hierarchical model enables the design of a
modular topology using “building blocks” that are scalable and allow the network to meet evolving
The hierarchical model is based on a modular design, which is easy to scale, understand, and
troubleshoot because it follows a deterministic traffic pattern. The principle advantages of the
hierarchical model are:...
This is a written lab and is to be performed without the aid of an electronic calculator.
ABC Manufacturing has acquired a Class B address, 172.16.0.0. The company needs to create a subnetting scheme to provide the following:
• 36 subnets with at least 100 hosts
• 24 subnets with at least 255 hosts
• 10 subnets with at least 50 hosts
It is not necessary to supply an address for the WAN connection since it is supplied by the Internet service provider.
Parts 1 to 5, for each network topology: Determine the number of subnets; Design an appropriate addressing scheme; Assign addresses and subnet mask pairs to device interfaces; Examine the use of the available network address space and future growth potential.
Network reconnaissance cannot be prevented entirely. If Internet Control Message Protocol
(ICMP) echo and echo-reply is turned off on edge routers, ping sweeps can be stopped, but
at the expense of network diagnostic data. However, port scans can easily be run without
full ping sweeps; they just take longer because they need to scan IP addresses that might
not be live. Intrusion detection systems (IDSs) at the network and host levels can usually
notify an administrator when a reconnaissance attack is underway.
The BACnet protocol currently uses the connectionless User Datagram Protocol (UDP)
for both Annex H and BACnet/IP communications. However, it is possible that Trans-
mission Control Protocol (TCP) transport will be utilized for some service in the future,
and so threats specific to TCP have been included. Even if TCP/IP is never used as part
of the BACnet protocol, it still can be used to gain access to the building control system
web servers, get access through the corporate firewall, and be used for denial of service
attacks on the external network on which the BCS may depend.
The terminal networks of the various and competing network operators (of which there were 30 at
year-end 2001) are connected to the banking industry’s centres for the authorisation of electronic
payment by debit card in the electronic cash system. By the end of 2001, following a continuous
increase, about 306,000 electronic cash terminals had been installed (including electronic cash offline)
- mainly in petrol stations and retail outlets.
After completing this chapter, students will be able to: Explain syslog operation in a small-to-medium-sized business network, configure syslog to compile messages on a small-to-medium-sized business network management device, explain syslog operation in small-to-medium-sized business network,... Inviting you to refer lecture for more information.
After studying this chapter you should be able to: Explain how network documentation is developed and used to troubleshoot network issues; describe the general troubleshooting process; compare troubleshooting methods that use a systematic, layered approach;... Inviting you to refer lecture for more information.