With Cisco phones and switches, what is the proper way to set up the switch to allow a PC and phone at the same time, so that both the PC and phone work?

With Cisco phones and switches, what is the proper way to set up the switch to allow a PC and phone at the same time, so that both the PC and phone work?

• switchport access vlan #, switchport voice vlan #
• switchport access voice vlan #
• This is not possible
• Use the HTTP webUI to configure the switches 

EXPLANATION

Switchport mode access
switchport access vlan (data)
switchport voice (voice vlan)
spanning-tree portfast

CDP will figure out if it is a phone or not and allow clients plugged in behind the phone (through the phone) to use the data vlan


The switch uses CDP to identify the other device as a ip phone and will automatically place that traffic on the voice vlan.  If this is not a Cisco phone you will have hardcode the phone to tag its traffic as vlan x.

Read More

A higher end laser printer is making odd marks even when you print the printer config. What is the best way to find the culprit? And you can't tell or your guess was wrong based on the mark spacing and relating to the roller size.

A higher end laser printer is making odd marks even when you print the printer config. What is the best way to find the culprit? And you can't tell or your guess was wrong based on the mark spacing and relating to the roller size.

• Use a half stop test.
• Try printing using another computer or driver.
• Reboot the computer
• Throw it out because you don't want to fix it. 

EXPLANATION

 Printer problem, it may be caused by an outdated or a faulty printer driver. Outdated printer drivers cause major compatibility issues and render your device useless.

Or restart the spooler service

net stop spooler
net start spooler
exit

 

Read More

DHCP does not work on subnets attached to a router that don't have a DHCP server on them. What is the most probable cause?

DHCP does not work on subnets attached to a router that don't have a DHCP server on them. What is the most probable cause?

• No DHCP relay is set on the router interfaces
• The DHCP server is down
• You need a DHCP server for every subnet and vlan
• This is not possible 

EXPLANATION

Dynamic Host Configuration Protocol (DHCP) servers provide configuration parameters to DHCP clients. DHCP supplies network settings, including the host IP address, the default gateway, and a DNS server. When DHCP clients and associated servers do not reside on the same IP network or subnet, a DHCP relay agent can transfer DHCP messages between them. The DHCP relay agent operates as the interface between DHCP clients and the server. It listens for client requests and adds vital configuration data, such as the client's link information, which is needed by the server to allocate the address for the client. When the DHCP server responds, the DHCP relay agent forwards the reply back to the DHCP client.  

SOURCE

 https://www.cisco.com/c/en/us/td/docs/app_ntwk_services/data_center_app_services/ace_appliances/vA4_1_0/configuration/rtg_brdg/guide/rtbrgdgd/dhcp.pdf 

 

Read More

What is VOIP?

What is VOIP?

• A method of delivering voice and multimedia communications over the internet
• A method of segregating multiple networks over the same physical infrastructure
• A platform that allows you to manage virtual machine on a host
• A telephone answering machine and call returning service offered by telecoms providers

EXPLANATION

Voice over Internet Protocol (also voice over IP, VoIP or IP telephony) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.
The terms Internet telephony, broadband telephony, and broadband phone service specifically refer to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN).

SOURCE

https://en.wikipedia.org/wiki/Voice_over_IP

Read More

In a database, cardinality refers to:

In a database, cardinality refers to:

• Which command gets executed first
• How many columns a table contains
• How many rows a table contains
• How many unique values are in a column of a table 

 

 

EXPLANATION

In databases, cardinality refers to the how many unique data values each column contains. High cardinality columns contain unique data values. Low cardinality columns contain few unique values.

SOURCE

http://www.sqlservercentral.com/blogs/matthew-mcgiffen-dba/2017/06/20/statistics-and-cardinality-estimation/

Read More

What wireless attack is able to trick devices/users into connecting to it by appearing as trusted network that they have connected to in the past.

What wireless attack is able to trick devices/users into connecting to it by appearing as trusted network that they have connected to in the past.

• Spoofing
• Evil Twin
• Replay
• Disassociation 

EXPLANATION

Evil Twin is the correct answer. Disassociation (or deauth) attacks send special packets to kick a client device off a network and can be used to help connect a target to the evil twin.
Replay attacks are replaying previously captured packets on a network. And though the attacker is spoofing the name of a trusted network the attack is referred to as an evil twin.

SOURCE

https://en.wikipedia.org/wiki/Evil_twin_(wireless_networks)

Read More

What is the standard IRQ assignment for COM2?

What is the standard IRQ assignment for COM2?

• IRQ 0
• IRQ 7
• IRQ 4
• IRQ 3

EXPLANATION

An IRQ (Interrupt ReQuest) is a physical connection on the motherboard through which a piece of hardware communicates with the CPU and the OS; the CPU responds through an I/O (input/output) memory address. The so-called Standard IRQ assignments date back to the early days of DOS and Windows 3.x.
In the bad old days, IRQs had to be assigned manually, either by means of physical switches, jumpers, or with software. Even now, you may occasionally have to assign an IRQ manually, although it doesn't happen often. Also, newer computers have more than 16 IRQs and the hardware and software can share IRQs without fighting. Usually.
IRQ Assignment
0 system timer*
1 keyboard*
2 link to second IRQ controller*
3 serial port 2 (COM2; usually the modem, if present)
4 serial port 1 (COM1; usually the [serial] mouse, if present)
5 available, OR sound card (if present), OR parallel port 2 (LPT2)
6 floppy disk controller*
7 parallel port 1 (LPT1) = the printer
8 real-time clock*
9 available (may appear as IRQ 2)
10 available
11 available
12 available, OR PS/2 mouse (if present)
13 math coprocessor*
14 primary IDE controller (first/main hard drive)*

15 available, OR secondary IDE controller (other hard drives/CDROM, etc.)

Read More