access list project

SIX WEEKS INDUSTRIAL TRAININGSIX WEEKS INDUSTRIAL TRAINING1

Guided By :-Mr Barinder Singh

Presented By :-

2

NETMAX TECHNOLOGIES as an organization is established in 2001 in the field of Network Support, Network training, Software training and Embedded systems.

NETMAX TECHNOLOGIES also provide Technical Research & Development support and consultancy to some companies.

NETMAX TECHNOLOGIES provide the following Courses in IT & Embedded Systems given below:

  Network Training:

CISCO CCNA, CCNP RED HAT LINUX 5 WINDOWS 2000, 2003 (MCP,MCSA & MCSE) MCITP 2008.

3

Software Training:C++C JAVA ( CORE JAVA & ADVANCE JAVA)ASP.NET We provide Technical support and consultancy to electronics

companies in the field of Embedded micro controllers like 8 bit and 16 bit family based embedded system design, analog systems design. Power electronics including dc/dc converters, ac/dc converters, thyristor firing based circuit, battery charging and monitor circuits etc.

4

5

Manage IP traffic as network access grows Filter packets as they pass through the router

6

ACLs are lists of conditions that are applied to traffic traveling across a router's interface. 

These lists tell the router what types of packets to accept or deny.

Acceptance and denial can be based on specified conditions.

ACLs can be configured at the router to control access to a network or subnet.

Some ACL decision points are source and destination addresses, protocols, and upper-layer port numbers.

ACLs are lists of conditions that are applied to traffic traveling across a router's interface. 

These lists tell the router what types of packets to accept or deny.

Acceptance and denial can be based on specified conditions.

ACLs can be configured at the router to control access to a network or subnet.

Some ACL decision points are source and destination addresses, protocols, and upper-layer port numbers.

7

The following are some of the primary reasons to create ACLs:

Limit network traffic and increase network performance.

Provide traffic flow control.

Provide a basic level of security for network access.

Decide which types of traffic are forwarded or blocked at the router interfaces

For example: Permit e-mail traffic to be routed, but block all telnet traffic.

If ACLs are not configured on the router, all packets passing through the router

will be allowed onto all parts of the network.

The following are some of the primary reasons to create ACLs:

Limit network traffic and increase network performance.

Provide traffic flow control.

Provide a basic level of security for network access.

Decide which types of traffic are forwarded or blocked at the router interfaces

For example: Permit e-mail traffic to be routed, but block all telnet traffic.

If ACLs are not configured on the router, all packets passing through the router

will be allowed onto all parts of the network.

8

Different access list for Telnet

When configuring ISDN you need to use access list

Implicit deny at bottom

All restricted statements should be on first

There are two types

Standard

Extended

Different access list for Telnet

When configuring ISDN you need to use access list

Implicit deny at bottom

All restricted statements should be on first

There are two types

Standard

Extended

9

N1 N2

N3 N4 N5 N6

192.168.12.0

A

B C

192.168.34.0192.168.56.0

192.168.12.2 192.168.12.3

10

SRC IP AddressDEST IP AddressProtocol typeSRC PortDEST Port

SRC IP AddressDEST IP AddressProtocol typeSRC PortDEST Port

The first 2 bytes in the TCP/UDP header are the source port numberThe next 2 bytes in the TCP/UDP header are the Destination port number

The first 2 bytes in the TCP/UDP header are the source port numberThe next 2 bytes in the TCP/UDP header are the Destination port number

11

StandardChecks source addressPermits or denies entire protocol suite

ExtendedChecks source and destination addressGenerally permits or denies specific

protocols.

StandardChecks source addressPermits or denies entire protocol suite

ExtendedChecks source and destination addressGenerally permits or denies specific

protocols.

12

Standard IP lists (1-99) test conditions of all IP packets from source addresses.

Extended IP lists (100-199) test conditions of source and destination addresses, specific TCP/IP protocols, and destination ports.

Standard IP lists (1300-1999) (expanded range). Extended IP lists (2000-2699) (expanded range).

Standard IP lists (1-99) test conditions of all IP packets from source addresses.

Extended IP lists (100-199) test conditions of source and destination addresses, specific TCP/IP protocols, and destination ports.

Standard IP lists (1300-1999) (expanded range). Extended IP lists (2000-2699) (expanded range).

13

The full syntax of the standard ACL command is:

Router(config)#access-list access-list-number {deny | permit} source [source-wildcard ]

The no form of this command is used to remove a standard ACL. This is the syntax:Router(config)#no access-list access-list-number

The full syntax of the standard ACL command is:

Router(config)#access-list access-list-number {deny | permit} source [source-wildcard ]

The no form of this command is used to remove a standard ACL. This is the syntax:Router(config)#no access-list access-list-number

Config# Access-list 1 deny 192.168.1.0 0.0.0.255Config# access-list 1 permit any Config# Access-list 1 deny 192.168.1.0 0.0.0.255Config# access-list 1 permit any

14

Access-list 99 permit 192.168.1.1 wildcard maskAll 32 bits of an IP Address can be filteredWildcard inverse mask0=must match1= ignore

Access-list 99 permit 192.168.1.1 wildcard maskAll 32 bits of an IP Address can be filteredWildcard inverse mask0=must match1= ignore

MASK (192.168.1.1) Matching IP

0.0.0.0 (host) 192.168.1.1

0.0.0.255 192.168.1.0-255

0.0.255.255 192.168.0-255.0-255

0.255.255.255 192.0-255.0-255.0-255

255.255.255.255 0-255.0-255.0-255.0-255 (any)

15

Access-list 1 permit 200.0.0.9 0.0.0.0

Or

permit host 200.0.0.9

Access-list 1 permit 200.0.0.9 0.0.0.0

Or

permit host 200.0.0.9

Access-list 1 permit 0.0.0.0 255.255.255.255

Or

permit any

Access-list 1 permit 0.0.0.0 255.255.255.255

Or

permit any

16

17

• If no access list statement matches, then discard the packet.

18

First Hit or Best Fit?1. Access-list 99 deny host 192.168.1.1 0.0.0.0

access-list 99 permit any 255.255.255.255

2. Access-list 99 permit 192.168.1.0 0.0.0.255Access-list 99 deny host 192.168.1.1access-list 99 permit any

3. Access-list 99 deny host 192.168.1.1

4. Implicit deny at the end of every ACL

First Hit or Best Fit?1. Access-list 99 deny host 192.168.1.1 0.0.0.0

access-list 99 permit any 255.255.255.255

2. Access-list 99 permit 192.168.1.0 0.0.0.255Access-list 99 deny host 192.168.1.1access-list 99 permit any

3. Access-list 99 deny host 192.168.1.1

4. Implicit deny at the end of every ACL

19

ACLs are created in the global configuration mode. There are many different

types of ACLs including standard, extended, IPX, AppleTalk, and others. When

configuring ACLs on a router, each ACL must be uniquely identified by assigning a

number to it. This number identifies the type of access list created and must fall

within the specific range of numbers that is valid for that type of list.

Since IP is by far the most popular routed protocol, addition ACL numbers have been added to newer router IOSs. Standard IP: 1300-1999Extended IP: 2000-2699

20

{ in | out }

21

Account should be denied access to Sales

To steps to configure•Create a standard Access list•Apply ACL to proper interface inbound or outbound

192.168.0.5255.255.255.252

192.168.0.9255.255.255.252

A B

S0 S0

E0

E0

192.168.0.18255.255.255.248

S0 S1192.168.0.17255.255.255.248

192.168.0.6255.255.255.252

192.168.0.10255.255.255.252

192.168.0.33255.255.255.240

192.168.0.34255.255.255.240

22

A B

S0 S0

E0

E0

192.168.0.18255.255.255.248

S0 S1192.168.0.17255.255.255.248

192.168.0.5255.255.255.252

192.168.0.6255.255.255.252

192.168.0.9255.255.255.252

192.168.0.10255.255.255.252

192.168.0.33255.255.255.240

192.168.0.34255.255.255.240

Config# Access-list 1 deny 192.168.0.18 0.0.0.7Config# access-list 1 permit any

Config#int e 0 Config-if# ip access-group 1 out

Extended ACLs23

Extended ACLs are used more often than standard ACLs because they provide a greater range of control.

Extended ACLs check the source and destination packet addresses as well as being able to check for protocols and port numbers.

At the end of the extended ACL statement, additional precision is gained from a field that specifies the optional Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) port number.

Logical operations may be specified such as, equal (eq), not equal (neq), greater than (gt), and less than (lt), that the extended ACL will perform on specific protocols.

Extended ACLs use an access-list-number in the range 100 to 199 (also from 2000 to 2699 in recent IOS).

24

Access-list acl# {permit/Deny}

• Protocol• Src IP src

WCM• Dst IP dst

WCM• Opetrator port

• Protocol– OSPF– EIGRP– ICMP– TCP– UDP

RPIf you need to Block a routing protocol

IP• Operator

– eq– gt– lt– neq

25

26

28

192.168.0.34 should be denied FTP of 192.168.0.18

On Router R1Config# Access-list 100 deny tcp 192.168.0.34 0.0.0.0

192.168.0.18 0.0.0.0 eq 21Config# access-list 100 permit IP any any

Config#int s0Config-if# ip access-group 100 IN

S0

S0

E0E0

A B

192.168.0.18 should be denied website of 192.168.0.34

On Router R3Config# Access-list 100 deny tcp 192.168. 0.18 0.0.0.0

192.168.0.34 0.0.0.0 eq 80Config# access-list 100 permit IP any any

Config#int s0Config-if# ip access-group 100 IN

S1S0

192.168.0.18255.255.255.248

192.168.0.17255.255.255.248

192.168.0.5255.255.255.252

192.168.0.6255.255.255.252

192.168.0.9255.255.255.252

192.168.0.10255.255.255.252

192.168.0.33255.255.255.240

192.168.0.34255.255.255.240

29

access-list 101 deny tcp any any eq 21

access-list 101 permit ip any any

or

access-list 101 deny tcp any any eq ftp

access-list 101 permit ip any any

30

For extended access list apply near to the source For standard access list apply near to the destination

31

IP named ACLs were introduced in Cisco IOS Software Release 11.2, allowing standard and extended ACLs to be given names instead of numbers.

The characteristics of named accesslist: Identify an ACL using an alphanumeric name. You can delete individual statements in a named access

list Named access lists must be specified as standard or

extended You can use the ip access-list command to create

named access lists.

Named ACLs are not compatible with Cisco IOS releases prior to Release 11.2.

The same name may not be used for multiple ACLs.

32

Numbered Access list did not give you any hint, What is filtered

Named ACL’s are both basic and advanced filtering tool

Name cannot start with a number or !

Cannot have space in the name

Should not have ? Character anywhere in the name

Name is case sensitive

33

R1(config)#ip access-list standard blocksalesR1(config-std-nacl)#deny 172.16.40.0

0.0.0.255R1(config-std-nacl)#permit anyR1(config-std-nacl)#exitR1(config)#^ZR1#

#Int e 0#Ip access-group blocksales out

34

35

Standard IP access lists should be applied closest to the destination. Extended IP access lists should be applied closest to the source. Use the inbound or outbound interface reference as if looking at the port from inside the router. Statements are processed sequentially from the top of list to the bottom until a match is found, if no match is found then the packet is denied. There is an implicit deny at the end of all access lists. This will not appear in the configuration listing. Access list entries should filter in the order from specific to general. Specific hosts should be denied first, and groups or general filters should come last. Never work with an access list that is actively applied. New lines are always added to the end of the access list. A no access-list x command will remove the whole list. It is not possible to selectively add and remove lines with numbered ACLs. Outbound filters do not affect traffic originating from the local router.

According to our project we are having three locations at pta.,chd and delhi having two departments i.e sale and mkt in each respectively. The three different locations are made to communicate with each other through the use of different routing protocols.For securities we create the rules on router to control the traffic according to the requirement.The working of this project is also shown in the simmulator.

We want that sale dept systems can communicate with marketing dept,so we will take a manageable switch and create vlans for each dept and assign the ports to the vlan and attach the particular dept sys in its vlan. The broadcasting remains in the vlan

Configuration of vlan :Switch>enableSwitch#vlan databaseSwitch(vlan)# vlan 2 name saleSwitch(vlan)# vlan 3 name mkt.Switch(vlan)exitSwitch# config tSwitch(config)# int range f0/1 , f0/2Switch(config)# switchport access vlan 2Switch(config)# exitSwitch#config tSwitch(config)# int range f0/3 , f0/4Switch(config)# switchport access vlan 3Switch(config)# exitSwitch#wr

Suppose we want that vlan2 communicates with vlan3, so we will take a router and configure intervlan on it.

Configuration of intervlan on router:Router>enableRouter#config tRouter(config)#hostname patialapatiala(config)#int f0/0patiala(config)#no shutdown Patiala(config)#int f0/0.1Patiala(config)#encapsulation dot1q 2Patiala(config)#ip address 192.168.10.1 255.255.255.0Patiala(config)#no shutdownPatiala(config)#int f0/0.2 Patiala(config)#encapsulation dot1q 3Patiala(config)#ip address 192.168.11.1 255.255.255.0Patiala(config)#no shutdownPatiala(config)#exitPatiala(config)#wr

After doing this all the sale dept systems communicate with mkt dept. systems.Now if we want that the following sale dept systems can’t communicate with mkt dept systems configure with ip 192.168.13.2Sale dept system 192.168.10.2 ,192.168.10.16. For this we will create the acls on router to manage the traffic

How to configure the acls:patiala > enablePatiala #config tPatiala (config)#access – list 130 deny ip 192.168.10.2 0.0.0.0 192.168.13.2 0.0.0.0Patiala (config)#access – list 130 deny ip 192.168.10.16 0.0.0.0 192.168.13.2 0.0.0.0Patiala (config)# access – list 130 permit ip any any

For applying these acls we use the interface through which the data is sent and received on the network.Patiala (config )#int f0/0.1Patiala (config)#ip access –group 130 inPatiala (config)#exitPatiala#wr

We are having the three companies on the different locations and we will configure the router,switches in the same way as we configure on Patiala router but we will also control the traffic on the different locations so that some Patiala systems can’t communicate with some chd and some delhi systems.

For example we want that the system with ip 192.168.11.2 i.e at pta location can’t communicate with the system with ip 192.168.14.2 and 192.168.17.2 which are at chd and delhi locations respectively.

For this we will again create the acls on router to manage the traffic.

patiala > enablePatiala #config tPatiala (config)#access – list 130 deny ip 192.168.11.2 0.0.0.0 192.168.14.2 0.0.0.0Patiala (config)#access – list 130 deny ip 192.168.11.2 0.0.0.0 192.168.17.2 0.0.0.0Patiala (config)# access – list 130 permit ip any anyFor applying these acls we use the interface through which the data is sent and received on the networkPatiala (config )#int f0/0.2Patiala (config)#ip access –group 130 inPatiala (config)#exitPatiala#wr

44