Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

31 Days to CCNA > Day 10 - ACL Concepts > Flashcards

Day 10 - ACL Concepts Flashcards

1
Q

An ACL is a router __________ __________ (that is, it’s a list of ___________)

A

Configuration Script
Statements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

ACLs control whether a router permits or denies packets to pass, based on criteria in the what?

A

Packet header

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

To determine whether a packet is permitted or denied, it is tested against the ACL statement in what order?

A

Sequential order

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When an ACL statement matches, do any other statements get evaluated?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is at the bottom of every ACL?

A

An implicit deny any statement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

If a packet doesn’t match any of the statements in the ACL, what happens to it?

A

It’s dropped

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

ACLs use what kind of logic?

A

First match logic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

If a packet matches one line in the ACL, the router takes the action listed in that line of the ACL and does what with the rest of the ACL statements?

A

Ignores them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What two types of ACLs are there?

A

Standard IPv4 ACLs
Extended IPv4 and Extended IPv6 ACLs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What two methods are there to identify both standard and extended ACLs?

A

Numbered IPv4 ACLs
Named IPv4 and Named IPv6 ACLs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the difference between standard ACLs and Extended ACLs?

A

Standard ACLs filter traffic based on source address only

Extended ACLs filter traffic based on source and destination address, specific protocols and source and destination TCP and UDP ports

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What do numbered ACLs use to identify themselves?

A

They use a number for identification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do named ACLs use to identify themselves?

A

They use a descriptive name or number for identification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Standard numbered and standard named ACLs only look for matching what?

A

Source addresses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Extended numbered and extended named ACLs look for matching what?

A

Source and Dest IP
Source and Dest Port

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the number range for standard IP ACLs?

A

1-99

17
Q

What is the number range for Extended IP ACLs?

A

100-199

18
Q

What is the number range for expanded standard IP ACLs?

A

1300-1999

19
Q

In addition to using more memorable names, using named ACLs instead of numbered ACLs enable to you __________ individual statements in a named IP access list

A

delete

19
Q

What is the number range for expanded extended IP ACLs?

A

2000-2699

20
Q

What version of IOS Software release did IP access list entry sequence numbering get introduced with?

A

12.3

21
Q

How many ACLs are allowed per protocol, per direction, and per interface

A

1

22
Q

How should you organize the ACL statements?

A

Top down with more specific references appearing before more general ones

23
Q

You should always create the ACL before __________ it to an interface

A

Applying

24
Q

You typically should place extended ACLs as close to what?

A

The source traffic that you want to deny

25
Q

What does a wildcard mask of 0.0.0.0 mean?

A

It means the subnet mask is 255.255.255.255 and that the IP address before the mask is the only IP being targeted.

26
Q

Does an Extended ACL have a default wildcard mask?

A

No, you have to specify a wildcard mask with an extended ACL

27
Q

What is this Extended ACL doing?

R1(config)#access-list 100 permit tcp 10.10.10.0 0.0.0.255 gt 49151 10.10.50.10 0.0.0.0 eq telnet

A

It’s an extended ACL that will permit telnet TCP traffic from the subnet of 10.10.10.0/24 with a source port greater than 49151 going to a destination address of 10.10.50.10

28
Q

Write an Access Control Entry for this scenario:

Access List number of 100 that permits telnet TCP traffic from the subnet of 10.10.10.0/24 with a source port greater than 49151 going to a destination address of 10.10.50.10

A

access-list 100 permit tcp 10.10.10.0 0.0.0.255 gt 49151 10.10.50.10 0.0.0.0 eq telnet

29
Q

What does access-list 100 deny ip 10.10.10.0 0.0.0.255 10.10.50.0 0.0.0.255 represent?

A

This is denying ALL traffic from the source subnet of 10.10.10.0/24 to the destination network of 10.10.50.0/24

30
Q

What is this ACE telling us:

access-list 100 deny tcp host 10.10.10.10 10.10.20.0 0.0.0.255 eq www log

A

It’s an extended Access Control Entry with a number of 100
Deny TCP traffic from 10.10.10.10 that is going TO the destination network of 10.10.20.0/24 with a destination port of 80(www) and we want log it to the console or an external monitoring service

31
Q

If you’ve created your ACL with the Access Control Entries, what do you need to do to actually get them to work?

A

You need to enable it on the interface or VLAN with the access-group command

32
Q

What increments are ACLs numbered in?

A

10

33
Q

True or False: All traffic is denied except what is explicitly allowed due to the implied deny any any rule at the bottom the of ALL ACLs

A

True

34
Q

If you want to reverse the implicit deny any any rule so that ALL traffic is permitted except what is explicitly denied, how would you achieve this?

A

Add a permit any rule at the bottom of your entries

35
Q

Which would have precedence? An explicit permit any rule at the bottom of an ACL or an implicit deny any any at the bottom of the ACL?

A

The permit any rule would take precedence because it would be above the deny any any rule implicitly at the bottom

31 Days to CCNA (27 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions