CS610 Computer Networks Solved Quiz Or Solved MCQ's

Question # 1 of 10 ( Start time: 07:49:09 PM )  Total Marks: 1

Jitter is significance for ------------------

Select correct option:

 Voice

 Video

 Data

 All of above

Question # 2 of 10 ( Start time: 07:49:31 PM )  Total Marks: 1

Which one of the following is a property of dynamic routing?

Select correct option:

 It is inflexible

 It has low network overload

 It can work around network failure

 All of the above

Question # 3 of 10 ( Start time: 07:50:32 PM )  Total Marks: 1

Which of the following statements is incorrect?

Select correct option:

 Repeaters can recognize frame formats, they amplify and retransmit the electrical signal

 We cannot increase the maximum cable length as many times as we wish by just adding repeaters

 Repeaters do not recognize frame formats, they just amplify and retransmit the electrical signal

 None of these is incorrect

Question # 4 of 10 ( Start time: 07:51:10 PM )  Total Marks: 1

Which of the following statement is true regarding ATM?

Select correct option:

 It is a single technology for voice, video and data

 It has low jitter and high capacity.

 It uses fixed size, small cells, 48 octet’s data

 All of the above

Question # 5 of 10 ( Start time: 07:51:33 PM )  Total Marks: 1

Djikstra’s algorithm is used to compute the……………….

Select correct option:

 shortest path between two nodes

 number of nodes used in the network

 distance between different nodes

 none of the above

Question # 6 of 10 ( Start time: 07:52:52 PM )  Total Marks: 1

Frame relay is………………….

Select correct option:

 Connection oriented service

 Connectionless service

 It is typically ranges from 5Mbps to 1000Mbps.

 None of the above

Question # 7 of 10 ( Start time: 07:53:30 PM )  Total Marks: 1

Which of the following statement is wrong regarding PVC?

Select correct option:

 PVC last as long as the customer pay the periodic fee for its use.

 Forwarding tables are automatically restored after power of equipment failure.

 Forwarding table entries for PVC’s are dynamically configured.

 All of the above are wrong

Question # 8 of 10 ( Start time: 07:54:41 PM )  Total Marks: 1

ATM is a single technology designed to meet the goals of both -------- and -----------.

Select correct option:

 LAN & PAN

 LAN & WAN

 LAN & MAN

 All of above

Question # 9 of 10 ( Start time: 07:55:01 PM )  Total Marks: 1

To span long distances or many computers, networks must replace shared medium with............

Select correct option:

 segment transformation

 fiber optices

 packet switches

 None of the above

Question # 10 of 10 ( Start time: 07:55:31 PM )  Total Marks: 1

Which of the following technologies can extend the diameter of LAN medium?

Select correct option:

 Fiber optic

 Repeaters

 Diameter of LAN medium is not extendable

 Both, Fiber Optic and Repeaters

Question # 1 of 10 ( Start time: 07:57:40 PM )  Total Marks: 1

ATM is designed to work on ___________.

Select correct option:

 Twisted Pair

 Coaxial

 Radio Frequency

 Fiber

Question # 2 of 10 ( Start time: 07:58:30 PM )  Total Marks: 1

Djikstra’s algorithm is used to compute the……………….

Select correct option:

 shortest path between two nodes

 number of nodes used in the network

 distance between different nodes

 none of the above

Question # 3 of 10 ( Start time: 07:58:46 PM )  Total Marks: 1

Frame relay is………………….

Select correct option:

 Connection oriented service

 Connectionless service

 It is typically ranges from 5Mbps to 1000Mbps.

 None of the above

Question # 4 of 10 ( Start time: 07:59:05 PM )  Total Marks: 1

Which of the following statement is true regarding Distance-vector routing?

Select correct option:

 It is very simple to implement.

 Packet switch updates its own routing table first.

 It is used in RIP.

 All of the above

Question # 5 of 10 ( Start time: 07:59:44 PM )  Total Marks: 1

Which one is incorrect statement?

Select correct option:

 Hub wiring centralizes electronics and connections. It makes management easier

 No Transceiver allows computers to be powered off or disconnected from network without distracting other communication

 Transceiver may be located in an inconvenient place in any situation

 None of these

Question # 6 of 10 ( Start time: 08:00:37 PM )  Total Marks: 1

In ATM, header of a cell takes __________ of network capacity.

Select correct option:

 5%

 10%

 12%

 15%

Question # 7 of 10 ( Start time: 08:00:56 PM )  Total Marks: 1

A system with redundant bridges might have a problem with_______ in the system.

Select correct option:

 Filters

 Spanning Trees

 Addressing

 Loop

Question # 8 of 10 ( Start time: 08:01:17 PM )  Total Marks: 1

Most NICs contain _______________ circuitry that allows the NIC to operate independent of the CPU.

Select correct option:

 DMA (Direct Memory Access)

 Multiplexer

 Transceiver

 None of the give

Question # 9 of 10 ( Start time: 08:02:39 PM )  Total Marks: 1

Thin Ethernet is known as-------------

Select correct option:

 10Base2

 10Base5

 10BaseT

 All of above

Question # 10 of 10 ( Start time: 08:03:12 PM )  Total Marks: 1

The fiber-modem coverts digital data into _______ then transmits over the optical fiber

Select correct option:

 Pulses of light

 Electrons

 Electromagnetic signals

 None of these

Question # 1 of 10 ( Start time: 08:07:34 PM )  Total Marks: 1

Which one of the following is a property of dynamic routing?

Select correct option:

 It is inflexible

 It has low network overload

 It can work around network failure

 All of the above

Question # 2 of 10 ( Start time: 08:08:23 PM )  Total Marks: 1

The most important task a bridge performs is _______

Select correct option:

 Packet switching

 Line controlling

 Noise controlling

 Frame filtering

Question # 3 of 10 ( Start time: 08:09:37 PM )  Total Marks: 1

Which of the following statements is incorrect?

Select correct option:

 Repeaters can recognize frame formats, they amplify and retransmit the electrical signal

 We cannot increase the maximum cable length as many times as we wish by just adding repeaters

 Repeaters do not recognize frame formats, they just amplify and retransmit the electrical signal

 None of these is incorrect

Question # 4 of 10 ( Start time: 08:10:53 PM )  Total Marks: 1

Which of the following is a benefit of source independence?

Select correct option:

 It allows fast and efficient routing.

 Packet switch do not need to have complete information about all destinations

 Network functions even if topology changes

 All of the above

Question # 5 of 10 ( Start time: 08:13:55 PM )  Total Marks: 1

ATM is also called----------------

Select correct option:

 Label rewriting

 Label switching system

 Label rewriting and label switching system

 All of above

Question # 6 of 10 ( Start time: 08:15:28 PM )  Total Marks: 1

........ is effectively a very short Ethernet with very long AUI cables. It can be connected into larger Ethernet

Select correct option:

 RJ-45

 HUBS

 10Base-T

 None of these

Question # 7 of 10 ( Start time: 08:16:53 PM )  Total Marks: 1

Jitter is significance for ------------------

Select correct option:

 Voice

 Video

 Data

 All of above

Question # 8 of 10 ( Start time: 08:17:39 PM )  Total Marks: 1

Which of the following statement is true regarding Link-state routing?

Select correct option:

 Network topology is separated from route computation.

 Each switch builds its own routing tables.

 Link-state routing uses Djikstra’s algorithm.

 All of the above

Question # 9 of 10 ( Start time: 08:18:56 PM )  Total Marks: 1

In ATM, header of a cell takes __________ of network capacity.

Select correct option:

 5%

 10%

 12%

 15%

Question # 10 of 10 ( Start time: 08:19:45 PM )  Total Marks: 1

An exterior switch is one with which ………………….

Select correct option:

 Computers are attached

 No computer is attached

 hubs are attached externally

 None of the above

Question # 1 of 10 ( Start time: 08:25:28 PM )  Total Marks: 1

Which one of the following is a method for computing routing table information?

Select correct option:

 Manual entry

 Static routing

 Boot time routing

 None of the above

ATM is also called----------------

Select correct option:

 Label rewriting

 Label switching system

 Label rewriting and label switching system

 All of above

Question # 3 of 10 ( Start time: 08:27:03 PM )  Total Marks: 1

ATM offers high speed and ----------- delay.

Select correct option:

 High

 Low

 Moderate

 All of above

Question # 4 of 10 ( Start time: 08:27:26 PM )  Total Marks: 1

The maximum cable length of a LAN is _____

Select correct option:

 Fixed

 Unlimited

 Fixed and Unlimited in different conditions

 None of these

Question # 5 of 10 ( Start time: 08:27:45 PM )  Total Marks: 1

Most NICs contain _______________ circuitry that allows the NIC to operate independent of the CPU.

Select correct option:

 DMA (Direct Memory Access)

 Multiplexer

 Transceiver

 None of the given

Question # 6 of 10 ( Start time: 08:27:59 PM )  Total Marks: 1

The routing table in interior and exterior switches has which one of the following?

Select correct option:

 It should have next hop for each possible destination

 The next hop in table must be on shortest path to destination

 Both (a) and (b)

 None of the above

Question # 7 of 10 ( Start time: 08:28:40 PM )  Total Marks: 1

The routing table contains information about the ………………immediately around it.

Select correct option:

 topology of the network

 destination

 both of the above

 none of the above

Question # 8 of 10 ( Start time: 08:29:31 PM )  Total Marks: 1

Which one of the following is a property of static routing?

Select correct option:

 It is inflexible

 It is done at boot time

 It has low network overload

 All of the above

Question # 9 of 10 ( Start time: 08:30:49 PM )  Total Marks: 1

Which of the following statement is true regarding Distance-vector routing?

Select correct option:

 It is very simple to implement.

 Packet switch updates its own routing table first.

 It is used in RIP.

 All of the above

Question # 10 of 10 ( Start time: 08:31:30 PM )  Total Marks: 1

Jitter is significance for ------------------

Select correct option:

 Voice

 Video

 Data

 All of above

Question # 1 of 10 ( Start time: 08:38:29 PM )  Total Marks: 1

Which of the following statement is true regarding Distance-vector routing?

Select correct option:

 It is very simple to implement.

 Packet switch updates its own routing table first.

 It is used in RIP.

 All of the above

Question # 2 of 10 ( Start time: 08:38:56 PM )  Total Marks: 1

Djikstra’s algorithm is used to compute the……………….

Select correct option:

 shortest path between two nodes

 number of nodes used in the network

 distance between different nodes

 none of the above

Question # 3 of 10 ( Start time: 08:39:17 PM )  Total Marks: 1

A typical port on an ATM switch operates at __________ or higher.

Select correct option:

 OC-2 speed (155Gbps)

 OC-2 speed (1000Mbps)

 OC-3 speed (155Mbps)

 OC-3 speed (100Gbps)

Question # 4 of 10 ( Start time: 08:39:59 PM )  Total Marks: 1

Which of the following statement is wrong regarding PVC?

Select correct option:

 PVC last as long as the customer pay the periodic fee for its use.

 Forwarding tables are automatically restored after power of equipment failure.

 Forwarding table entries for PVC’s are dynamically configured.

 All of the above are wrong

Question # 5 of 10 ( Start time: 08:41:15 PM )  Total Marks: 1

Which one of the following is a property of dynamic routing?

Select correct option:

 It is inflexible

 It has low network overload

 It can work around network failure

 All of the above

Question # 6 of 10 ( Start time: 08:42:52 PM )  Total Marks: 1

________network topology is a bus but wiring topology is a star

Select correct option:

 10Base-T

 Ring

 10Base-W

 Star

Question # 7 of 10 ( Start time: 08:43:28 PM )  Total Marks: 1

Which of the following statement is true regarding Link-state routing?

Select correct option:

 Network topology is separated from route computation.

 Each switch builds its own routing tables.

 Link-state routing uses Djikstra’s algorithm.

 All of the above

Question # 8 of 10 ( Start time: 08:44:17 PM )  Total Marks: 1

The routing table contains information about the ………………immediately around it.

Select correct option:

 topology of the network

 destination

 both of the above

 none of the above

Question # 9 of 10 ( Start time: 08:44:47 PM )  Total Marks: 1

Which statement is incorrect according to 10Base-T standard of TP Ethernet?

Select correct option:

 This makes it cheaper and that ‘s why it is most useful technology of today

 It replaces AUI cable with twisted pair cable and thick coax with hub.

 10Base-T is a wiring scheme in a WAN with twisted pair cable.

 All statement are incorrect.

Question # 10 of 10 ( Start time: 08:45:58 PM )  Total Marks: 1

All destinations on same switch have same

Select correct option:

 Router

 Information

 Next hop

 None of the above

Question # 1 of 10 ( Start time: 07:49:09 PM )  Total Marks: 1

Jitter is significance for ------------------

Select correct option:

 Voice

 Video

 Data

 All of above

Question # 2 of 10 ( Start time: 07:49:31 PM )  Total Marks: 1

Which one of the following is a property of dynamic routing?

Select correct option:

 It is inflexible

 It has low network overload

 It can work around network failure

 All of the above

Question # 3 of 10 ( Start time: 07:50:32 PM )  Total Marks: 1

Which of the following statements is incorrect?

Select correct option:

 Repeaters can recognize frame formats, they amplify and retransmit the electrical signal

 We cannot increase the maximum cable length as many times as we wish by just adding repeaters

 Repeaters do not recognize frame formats, they just amplify and retransmit the electrical signal

 None of these is incorrect

Question # 4 of 10 ( Start time: 07:51:10 PM )  Total Marks: 1

Which of the following statement is true regarding ATM?

Select correct option:

 It is a single technology for voice, video and data

 It has low jitter and high capacity.

 It uses fixed size, small cells, 48 octet’s data

 All of the above

Question # 5 of 10 ( Start time: 07:51:33 PM )  Total Marks: 1

Djikstra’s algorithm is used to compute the……………….

Select correct option:

 shortest path between two nodes

 number of nodes used in the network

 distance between different nodes

 none of the above

Question # 6 of 10 ( Start time: 07:52:52 PM )  Total Marks: 1

Frame relay is………………….

Select correct option:

 Connection oriented service

 Connectionless service

 It is typically ranges from 5Mbps to 1000Mbps.

 None of the above

Question # 7 of 10 ( Start time: 07:53:30 PM )  Total Marks: 1

Which of the following statement is wrong regarding PVC?

Select correct option:

 PVC last as long as the customer pay the periodic fee for its use.

 Forwarding tables are automatically restored after power of equipment failure.

 Forwarding table entries for PVC’s are dynamically configured.

 All of the above are wrong

Question # 8 of 10 ( Start time: 07:54:41 PM )  Total Marks: 1

ATM is a single technology designed to meet the goals of both -------- and -----------.

Select correct option:

 LAN & PAN

 LAN & WAN

 LAN & MAN

 All of above

Question # 9 of 10 ( Start time: 07:55:01 PM )  Total Marks: 1

To span long distances or many computers, networks must replace shared medium with............

Select correct option:

 segment transformation

 fiber optices

 packet switches

 None of the above

Question # 10 of 10 ( Start time: 07:55:31 PM )  Total Marks: 1

Which of the following technologies can extend the diameter of LAN medium?

Select correct option:

 Fiber optic

 Repeaters

 Diameter of LAN medium is not extendable

 Both, Fiber Optic and Repeaters

Question # 1 of 10 ( Start time: 07:57:40 PM )  Total Marks: 1

ATM is designed to work on ___________.

Select correct option:

 Twisted Pair

 Coaxial

 Radio Frequency

 Fiber

Question # 2 of 10 ( Start time: 07:58:30 PM )  Total Marks: 1

Djikstra’s algorithm is used to compute the……………….

Select correct option:

 shortest path between two nodes

 number of nodes used in the network

 distance between different nodes

 none of the above

Question # 3 of 10 ( Start time: 07:58:46 PM )  Total Marks: 1

Frame relay is………………….

Select correct option:

 Connection oriented service

 Connectionless service

 It is typically ranges from 5Mbps to 1000Mbps.

 None of the above

Question # 4 of 10 ( Start time: 07:59:05 PM )  Total Marks: 1

Which of the following statement is true regarding Distance-vector routing?

Select correct option:

 It is very simple to implement.

 Packet switch updates its own routing table first.

 It is used in RIP.

 All of the above

Question # 5 of 10 ( Start time: 07:59:44 PM )  Total Marks: 1

Which one is incorrect statement?

Select correct option:

 Hub wiring centralizes electronics and connections. It makes management easier

 No Transceiver allows computers to be powered off or disconnected from network without distracting other communication

 Transceiver may be located in an inconvenient place in any situation

 None of these

Question # 6 of 10 ( Start time: 08:00:37 PM )  Total Marks: 1

In ATM, header of a cell takes __________ of network capacity.

Select correct option:

 5%

 10%

 12%

 15%

Question # 7 of 10 ( Start time: 08:00:56 PM )  Total Marks: 1

A system with redundant bridges might have a problem with_______ in the system.

Select correct option:

 Filters

 Spanning Trees

 Addressing

 Loop

Question # 8 of 10 ( Start time: 08:01:17 PM )  Total Marks: 1

Most NICs contain _______________ circuitry that allows the NIC to operate independent of the CPU.

Select correct option:

 DMA (Direct Memory Access)

 Multiplexer

 Transceiver

 None of the give

Question # 9 of 10 ( Start time: 08:02:39 PM )  Total Marks: 1

Thin Ethernet is known as-------------

Select correct option:

 10Base2

 10Base5

 10BaseT

 All of above

Question # 10 of 10 ( Start time: 08:03:12 PM )  Total Marks: 1

The fiber-modem coverts digital data into _______ then transmits over the optical fiber

Select correct option:

 Pulses of light

 Electrons

 Electromagnetic signals

 None of these

Question # 1 of 10 ( Start time: 08:07:34 PM )  Total Marks: 1

Which one of the following is a property of dynamic routing?

Select correct option:

 It is inflexible

 It has low network overload

 It can work around network failure

 All of the above

Question # 2 of 10 ( Start time: 08:08:23 PM )  Total Marks: 1

The most important task a bridge performs is _______

Select correct option:

 Packet switching

 Line controlling

 Noise controlling

 Frame filtering

Question # 3 of 10 ( Start time: 08:09:37 PM )  Total Marks: 1

Which of the following statements is incorrect?

Select correct option:

 Repeaters can recognize frame formats, they amplify and retransmit the electrical signal

 We cannot increase the maximum cable length as many times as we wish by just adding repeaters

 Repeaters do not recognize frame formats, they just amplify and retransmit the electrical signal

 None of these is incorrect

Question # 4 of 10 ( Start time: 08:10:53 PM )  Total Marks: 1

Which of the following is a benefit of source independence?

Select correct option:

 It allows fast and efficient routing.

 Packet switch do not need to have complete information about all destinations

 Network functions even if topology changes

 All of the above

Question # 5 of 10 ( Start time: 08:13:55 PM )  Total Marks: 1

ATM is also called----------------

Select correct option:

 Label rewriting

 Label switching system

 Label rewriting and label switching system

 All of above

Question # 6 of 10 ( Start time: 08:15:28 PM )  Total Marks: 1

........ is effectively a very short Ethernet with very long AUI cables. It can be connected into larger Ethernet

Select correct option:

 RJ-45

 HUBS

 10Base-T

 None of these

Question # 7 of 10 ( Start time: 08:16:53 PM )  Total Marks: 1

Jitter is significance for ------------------

Select correct option:

 Voice

 Video

 Data

 All of above

Question # 8 of 10 ( Start time: 08:17:39 PM )  Total Marks: 1

Which of the following statement is true regarding Link-state routing?

Select correct option:

 Network topology is separated from route computation.

 Each switch builds its own routing tables.

 Link-state routing uses Djikstra’s algorithm.

 All of the above

Question # 9 of 10 ( Start time: 08:18:56 PM )  Total Marks: 1

In ATM, header of a cell takes __________ of network capacity.

Select correct option:

 5%

 10%

 12%

 15%

Question # 10 of 10 ( Start time: 08:19:45 PM )  Total Marks: 1

An exterior switch is one with which ………………….

Select correct option:

 Computers are attached

 No computer is attached

 hubs are attached externally

 None of the above

Question # 1 of 10 ( Start time: 08:25:28 PM )  Total Marks: 1

Which one of the following is a method for computing routing table information?

Select correct option:

 Manual entry

 Static routing

 Boot time routing

 None of the above

ATM is also called----------------

Select correct option:

 Label rewriting

 Label switching system

 Label rewriting and label switching system

 All of above

Question # 3 of 10 ( Start time: 08:27:03 PM )  Total Marks: 1

ATM offers high speed and ----------- delay.

Select correct option:

 High

 Low

 Moderate

 All of above

Question # 4 of 10 ( Start time: 08:27:26 PM )  Total Marks: 1

The maximum cable length of a LAN is _____

Select correct option:

 Fixed

 Unlimited

 Fixed and Unlimited in different conditions

 None of these

Question # 5 of 10 ( Start time: 08:27:45 PM )  Total Marks: 1

Most NICs contain _______________ circuitry that allows the NIC to operate independent of the CPU.

Select correct option:

 DMA (Direct Memory Access)

 Multiplexer

 Transceiver

 None of the given

Question # 6 of 10 ( Start time: 08:27:59 PM )  Total Marks: 1

The routing table in interior and exterior switches has which one of the following?

Select correct option:

 It should have next hop for each possible destination

 The next hop in table must be on shortest path to destination

 Both (a) and (b)

 None of the above

Question # 7 of 10 ( Start time: 08:28:40 PM )  Total Marks: 1

The routing table contains information about the ………………immediately around it.

Select correct option:

 topology of the network

 destination

 both of the above

 none of the above

Question # 8 of 10 ( Start time: 08:29:31 PM )  Total Marks: 1

Which one of the following is a property of static routing?

Select correct option:

 It is inflexible

 It is done at boot time

 It has low network overload

 All of the above

Question # 9 of 10 ( Start time: 08:30:49 PM )  Total Marks: 1

Which of the following statement is true regarding Distance-vector routing?

Select correct option:

 It is very simple to implement.

 Packet switch updates its own routing table first.

 It is used in RIP.

 All of the above

Question # 10 of 10 ( Start time: 08:31:30 PM )  Total Marks: 1

Jitter is significance for ------------------

Select correct option:

 Voice

 Video

 Data

 All of above

Question # 1 of 10 ( Start time: 08:38:29 PM )  Total Marks: 1

Which of the following statement is true regarding Distance-vector routing?

Select correct option:

 It is very simple to implement.

 Packet switch updates its own routing table first.

 It is used in RIP.

 All of the above

Question # 2 of 10 ( Start time: 08:38:56 PM )  Total Marks: 1

Djikstra’s algorithm is used to compute the……………….

Select correct option:

 shortest path between two nodes

 number of nodes used in the network

 distance between different nodes

 none of the above

Question # 3 of 10 ( Start time: 08:39:17 PM )  Total Marks: 1

A typical port on an ATM switch operates at __________ or higher.

Select correct option:

 OC-2 speed (155Gbps)

 OC-2 speed (1000Mbps)

 OC-3 speed (155Mbps)

 OC-3 speed (100Gbps)

Question # 4 of 10 ( Start time: 08:39:59 PM )  Total Marks: 1

Which of the following statement is wrong regarding PVC?

Select correct option:

 PVC last as long as the customer pay the periodic fee for its use.

 Forwarding tables are automatically restored after power of equipment failure.

 Forwarding table entries for PVC’s are dynamically configured.

 All of the above are wrong

Question # 5 of 10 ( Start time: 08:41:15 PM )  Total Marks: 1

Which one of the following is a property of dynamic routing?

Select correct option:

 It is inflexible

 It has low network overload

 It can work around network failure

 All of the above

Question # 6 of 10 ( Start time: 08:42:52 PM )  Total Marks: 1

________network topology is a bus but wiring topology is a star

Select correct option:

 10Base-T

 Ring

 10Base-W

 Star

Question # 7 of 10 ( Start time: 08:43:28 PM )  Total Marks: 1

Which of the following statement is true regarding Link-state routing?

Select correct option:

 Network topology is separated from route computation.

 Each switch builds its own routing tables.

 Link-state routing uses Djikstra’s algorithm.

 All of the above

Question # 8 of 10 ( Start time: 08:44:17 PM )  Total Marks: 1

The routing table contains information about the ………………immediately around it.

Select correct option:

 topology of the network

 destination

 both of the above

 none of the above

Question # 9 of 10 ( Start time: 08:44:47 PM )  Total Marks: 1

Which statement is incorrect according to 10Base-T standard of TP Ethernet?

Select correct option:

 This makes it cheaper and that ‘s why it is most useful technology of today

 It replaces AUI cable with twisted pair cable and thick coax with hub.

 10Base-T is a wiring scheme in a WAN with twisted pair cable.

 All statement are incorrect.

Question # 10 of 10 ( Start time: 08:45:58 PM )  Total Marks: 1

All destinations on same switch have same

Select correct option:

 Router

 Information

 Next hop

 None of the above