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For questions about access control lists (ACLs). For instance, you want to limit network traffic to increase network performance or provide traffic flow control on your network device. ACLs also provide a basic level of security for network access by defining which part of the network/server/service ...

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2answers
56 views

Whether we usual use dot-decimal notation to represent network or IP by opposite mask?

Whether we usual use dot-decimal notation to represent network or IP by opposite mask? 10.10.10.0 0.0.0.255 # a network 10.10.10.0 255.255.255.0 # a IP Update if we represent a network, we can use ...
2
votes
1answer
36 views

Standard access list

I have following setup Vlan10 Pc1 192.168.10.20 Vlan20 Pc2 192.168.20.20 Vlan21 Pc2 192.168.21.20 Subnet :255.255.255.0 All connected to layer 3 switch I have ...
1
vote
1answer
74 views

how to deny ping from one direction but not the other using Access-list

Hello everyone. What I'm trying to do is to deny ping access from the 12.12.12.0 network to reach the 10.10.10.0 network but not deny ping access to go from 10.10.10.0 network and reach the 12.12.12....
0
votes
1answer
33 views

For ethernet with bandwidth B, how much time a node has to wait before sensing the channel after the first collision detected?

Let's say one node detected a collision at t=0, in B Mbps ethernet, how long will that node wait before sensing the channel again?
0
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1answer
73 views

Configuring static NAT on Cisco Router

I am trying to configure port forwarding on a Cisco 891F router given by an ISP and directly connected to servers in the 192.168.170.0/24 network. The ISP recommended using the ip nat inside source ...
3
votes
1answer
107 views

Multiple access lists on same vlan

I have 5 departments each with it's own vlan and i want some of them to ping some of them, and only want some of them to ping some of them back. Basically creating a hierarchy of vlans. Concretely, ...
3
votes
1answer
68 views

Access lists on vlans possible?

I have a building with some departments and each department has it's own vlan and subnet. so now all departments can communicate with each other, but i only want some of them to communicate with some. ...
3
votes
1answer
145 views

How do I permit only specific types of ICMP unreachable packets to be sent out from a Cisco IOS router? [closed]

I have a Cisco IOS router and want to permit only types of ICMP packets to be sent (type 8, code 0 and type 3, code 4). I tried putting an outbound ACL on the interface connecting to the Internet, but ...
3
votes
2answers
425 views

Cisco ASA 5510 implicit deny dropping traffic despite permit any ACL

I'm trying to allow VPN access through a specific public IP address on our company ASA. The ASA is currently configured with a /29 public IP address as follows: Interface Ethernet0/0 "outside" IP ...
0
votes
1answer
48 views

How do I assign machines to a VLAN based on machine authentication and user authentication using a NPS RADIUS server? [closed]

We have company-issued laptops that users can log into using smart cards. Using the Tunnel-PVT-Groupd-ID RADIUS element, we can assign the machine to a VLAN based on the authenticated user. However, ...
0
votes
1answer
28 views

Access Control Permissions

I have created a topolgy in packet tracer displaying two networks. I have cpnfigured VLANs on both of the networks and configured access control lists. However, I would like to configure access ...
2
votes
1answer
150 views

Waiting time in CSMA/CD doubt

I have a doubt regarding the time a particular node will wait after collision. I am using numerical values here so that one can easily understand my doubt. Suppose in a network, we have 2 nodes A ...
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votes
2answers
50 views

Can the data usage be Oriented by Consume of Demand?

Let's imagine that a LAN house, solve to charge financially your users, through of data usage consumption and not by time of use. It Is possible do control individually of assignment of data usage ...
3
votes
1answer
1k views

Access list with SNMP v3 Cisco

I was wondering if someone could help me with something. I am trying to set up SNMP v3 but with access control. Now, I have made the user and group. That's all fine, but I can't seem to get the access ...
1
vote
2answers
531 views

ACL on Internet Facing Interface

I have to set up and design a network as illustrated in: I need to configure ACLs on inside interface and outside one. However, when I implemented the access-lists, the flow of traffic was affected ...
0
votes
1answer
2k views

Access-list won't show all hit matches

I have access-lists in place. When i use the show ip access-list command, some of access-lists show counters (hit counts), and some don't. If I change the rule from permit to deny, interesting traffic ...
-1
votes
1answer
154 views

Extended access list conflict condition will it cause override?

Corp1(config)# access-list 10 permit tcp 192.168.33.3 0.0.0.0 177.22.242.23 0.0.0.0 eq www Corp1(config)# access-list 10 deny tcp 192.168.33.0 0.0.0.255 177.22.242.23 0.0.0.0 eq www Corp1(config)# ...
1
vote
2answers
715 views

How to apply firewall between stations connected to AP?

When I'm configuring wireless interface in RouterOS or in fact most of APs in general there are basically 2 options for controlling traffic between stations connected to AP - forward all, and don't ...
1
vote
2answers
2k views

Cisco router - deny access to host on port 8080, allow on 80

I'm designing a network with the following scheme: I have 5 vlans, 3 on S1 and 2 on S3. I'm currently concerned with making access list. Each vlan has a web server that is configured to listen on ...
1
vote
0answers
276 views

Optimizing access control lists on a Cisco SG500X-48 Small Business switch

I am trying to optimize the access control list rules on a Cisco SG500X-48 Small Business switch (on Layer 3). The general aim is to regulate the traffic between two VLANs (e.g., 10 and 30) in such a ...
0
votes
1answer
67 views

Wifi location based access control

I'd like to know if it is possible to determine a user's location with wi-fi and incorporate that into part of the identification, authentication and authorisation mechanism of the network? This ...
0
votes
2answers
870 views

ASA Firewall Can PING cannot SSH to switch on different interface

There are three interfaces, TRUST (security level 100), UNTRUST (security level 0), and DMZ (security level 50). I am on a network coming into the firewall via the UNTRUST interface. The switch I am ...
1
vote
1answer
8k views

ip ssh source-interface vlan - allow ssh from specific vlan not working

I am doing some practice on GNS3 related switch and want to allow SSH from specific VLAN Ex: vlan1 In GNS3 i used router with 16NM ethernet module to emulate switch, so i am using following command ...
3
votes
1answer
484 views

Open up port for one IP

I have a Cisco 1921 and I want to allow one WAN IP number (lets call it 1.2.3.4) to access a server on the LAN. My WAN interface is GigabitEthernet0/0 and my LAN interface is GigabitEthernet0/1. I ...
2
votes
1answer
530 views

Cisco ACL not working as expected

I've a client to which I want to deny access so that he cannot access my network host. There is this specified port that he scanned on my network host which I want to block (Port 137). Using NMAP, ...
1
vote
2answers
437 views

Multiple access and full/half duplex point-to-point links

In en.wikipedia.org/wiki/Channel_access_method, A channel-access scheme is based on a multiplexing method, that allows several data streams or signals to share the same communication channel or ...
1
vote
4answers
2k views

Is the root user on juniper switches useful?

On juniper switches is something like root user. Are there any things that must be done from that user? For what root user can be usefull? Or isn't usefull, and can be safetly disabled?
0
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1answer
312 views

Networking, dedicating bandwidth to specific networks

I need to configure a cisco router where 5mb will be split between 2 separate networks one for voice 1mb and one for data 4mb with voice being the main priority. The only way i can think of doing it ...
1
vote
1answer
1k views

Cisco VPN Clients Routing Over IPSec VPN - ACL?

I have remote access to a Cisco 2821 Router with a security firmware license in California with an IPSec tunnel going to a site in New York. On the New York side, there is a RFC 1918 IP scheme of 10.0....
2
votes
1answer
22 views

Limiting community member communication in PVLAN's

Is there a way to limit communication between community members in a PVLAN? Ex. Service provider ABC has 1000 clients, the clients with more than one VM to their name have their own community, ...
1
vote
2answers
71 views

Access Control List from a network to a specific device on another network.

I have been looking for an example online but could not find one so hopefully someone here might give me an example. I am trying to set up an ACL to block any entire network accessing a specific ...
1
vote
2answers
320 views

How to track un-authorized devices being connected to a private network?

The culture at one of our main branch offices is very open and loose. Historically when people have needed more ports in their space they could just grab a switch from someone with access to our ...