EMT Practice Test

1. Question Content...

---

Question1: A rackmount MCU can have two main control boards, support master-standby switching, and only need to configure one IP address.

Question2: The following description of the relationship between the RTCP port number and the RTP port number is correctly ( ).

Question3: In multimedia services, RTP is used for real-time data packet transmission, and RTCP is used to detect the quality of service of an RTP session. ( )

Question4: Only if the peer supports T.140, it can be implemented to send banners, subtitles or short messages to the specified venue in the T.140 mode.

Question5: The ARQ carries information about the node itself (IP address and port number), as well as information about the hard-called terminal (terminal number) and ( )

Question6: H.225 contains which of the following signalings ( ).

Question7: The following six main request messages are not part of the SIP protocol

Question8: In the hierarchical relationship of SIP structure, what are the following main items of the request message?

Question9: The HD terminal provides remote control interface, web management, remote SSH function, and assigns a user name and password to each service.

Question10: The following socket on the MCU is the default service network port. ()

Question11: RTCP can ensure the transmission quality well through RR, and each participant who receives data must send a RR.

Question12: The frequency response capacity of nature that the human ear can perceive can reach 20Hz-20KHz, using audio standards such as G.711, G.722, G.728, and the audio width is only available 50Hz-7KHz, so use AAC-LD method to solve this problem in high-definition video communication.

Question13: In 230.H.460 networking, what protocol does the tunnel between the terminal and the client GK follow? ()

Question14: Which of the following is part of the conference room design ( ).

Question15: When using the MCU wall riding mode, there is no need to add other devices traversed by public and private networks. ( )

Question16: How many ways can A venue join an IVK meeting?

Question17: The arrangement of luminaires requires the use of direct illumination to avoid diffuse reflection. ( )

Question18: The function of the redirect server is to map the addresses in the request to zero or more new addresses, which are returned to the client.

Question19: T140 captions are sent separately to the remote venue, displayed on the remote venue monitor, and superimposed on the local video image.

Question20: The opening process of the logical channel in the H323 protocol follows the principle of "who transmits, who opens". ( )

Question21: In the registration signaling process, the terminal initiates to GK which of the following messages represents a registration request ( ).

Question22: Dialogs can be divided into INVITE transactions and non-INVITE transactions, where the INVITE transaction in turn includes a request message and a response message.

Question23: T.140 Subtitles support sending and receiving subtitles from SIP, H.323 type terminals.

Question24: When scheduling the meeting, the "IP port resources are insufficient", and the check MCU corresponds to be online, and the number of 1P ports is sufficient. What could be wrong? ( )

Question25: The following description of nat mapping is correct () (3 answers).

Question26: RTCP is a real-time transport protocol that can be used as a way to detect and control data transmission, and this protocol cannot be upgraded to a large multicast (multicast) network.

Question27: Fe and GEO, GE1 IP addresses can not be in the same network segment, otherwise it will cause network failure, at this time the front panel ALM light is always on. ( )

Question28: In June 2002, SIP was adopted (), which is the core specification for the SIP protocol.

Question29: The following description of SIP registration, which one is wrong?

Question30: Video conferencing has certain requirements for lamps, and the lamps used require strong light efficiency, uniform and soft light, and make full use of diffuse reflection.

Question31: The FEC forward error correction algorithm is an algorithm that sends redundant data at the sending end and recovers the code stream based on the redundant data at the decoding end.

Question32: What are the correct items in the following description of the RTCP protocol?

Question33: The 310.H.460 protocol specifies that the public-private network traversal of the signaling portion is handled by ( ).

Question34: In the RTP specification (RFC3550), a total of ( ) types of RTCP reports are defined to report current control information.

Question35: The quality of digital audio depends on which factors. ( )

Question36: All MCUs under the same service area must have the same prefix number.

Question37: RTP is a real-time transmission control protocol: on multicast (multicast) or unicast (unicast) network services, provides end-to-end network transmission capabilities, suitable for applications to transmit real-time data, such as audio, video or simulation data.

Question38: Which of the following endpoints does not have MiniMCU functionality?

Question39: On top of UDP, the H.323 protocol is divided into (). (3 answers).

Question40: The following description of the H.323 call flow is correct

Question41: When querying the "System Status" on the web interface of the RSE6500, which of the following information cannot be obtained?

Question42: The H323 protocol ends up with the number 3 denoting ( ).

Question43: When sending and receiving T.140 subtitles, both parties who need to join support T.140 subtitles.

Question44: During a peer-to-peer number call, H.245 performs capability set matching before opening the logical channel.
()

Question45: What is the software format of the HD Video Terminal Upgrade Pack?

Question46: The recording server saves the stream sent by the MCU at ( )o

Question47:
When the speech codec capability is negotiated in the SIP protocol, the voice codec supported by the local device is provided, including PCMU and PCMA Based on the RTP message shown in the figure, it can be seen that the ( ) voice codec is selected.

Question48: Enabling SEC, the system can automatically adjust the network transmission and different error corrections of AV processing for the rich QOS mode of the IP network After enabling SEC, the anti-packet loss ability has been greatly improved ()

Question49: Multi-channel cascading supports auto-spin down function ().

Question50: Which of the following messages indicates that the SIP server failure could not complete the processing of the correct message. ( )

Question51: H.225 contains which of the following signalings (). (2 answers).

Question52: What does the RSE6500 offer?

Question53: There are ways to join an IVR meeting at a venue. (Fill in the blanks)

Question54: The terminal can send the conference content and the active image to the remote venue through the dual-stream desktop transmission function, and the desktop transmission format is directly consistent with the resolution size of the VGA input, which can support up to 1280*1024 The resolution of the desktop is sent.

Question55: During a peer-to-peer number call, H.245 performs capability set matching before opening the logical channel.
()

Question56: Which of the following is a mixing strategy ( ).

Question57: Terminal control mainly refers to the call signaling of the terminal, the negotiation of logic channels and AV capabilities, and the signaling of conference control.

Question58: Any color at the opposite end of the diameter of the color ring is called a complementary color. ( )

Question59: The H.323 six-step call process applies to all H.323 nodes.

Question60: RAS performs management functions, mainly including :() (3 answers).

Question61: In the H.323 protocol stack, what protocol is used by dual-streaming. ( )

Question62: A SIP message consists of a start-line header, a header consisting of one or more fields (riold), and a blank line that marks the end of the header ( CRLF) and as an optional message body (message boby) consists of. ( )

Question63: NAT is mapped in the following ways: Static NAT, Dynamic NAT, and NAPT.

Question64: The GK side hangs up the call in case of ( ).

Question65: When the MCU is working in wall riding mode, GE0 is registered with switch center and GE1 can only support IP address calling.

Question66: For request messages, which of the following is not required. ( )

Question67: Which of the following is not included in the main functions of the gateway gateway?

Question68: Non-T.140 subtitles only support sending and receiving subtitles from H.323 type terminals.

Question69: People convert the corresponding mechanical vibrations of sound into electrical signals, which are collectively referred to as audio signals.

Question70: The feed can be either the active image or the contents of the computer desktop. ( )

Question71: The H.460 protocol specifies that H.323 signaling parts of the public-private network traversal are handled. ()

Question72: The role of RTP in VoIP mainly includes: real-time transmission of media information, elimination of jitter, card performance, prevention of packet loss, in a certain situation can be transmitted DTMF signals, tones and signaling.

Question73: Forward error correction FEC, when both parties establish a call and detect more than 0.1% of the media stream loss within 10s, the super error correction function is enabled , super loan correction function, will be a part of the call bandwidth, used to transmit anti-packet loss of redundant code stream. ( )

Question74: As shown in the following figure, when the user presses the "+", "-" or arrow keys in the camera control interface of the terminal, he finds that the camera at this end does not respond, which of the following is not the possible cause of the problem

Question75: Adhoc Conferencing is a conferencing mode that allows you to create and join a meeting on the terminal side without an administrator.

Question76: The main roles of RTCP include ( ).

Question77: What elements are included in the SIP response message. ( )

Question78: mode, communication between public and private network devices is supported, and data does not need to go through a firewall.

Question79: MSDR is the master-slave decision to reject the message, the ability to exchange results that are inconsistent with the settings of this end, then reply to MSDR. ( )

Question80: Master-slave decisions are mainly used to prevent both parties from triggering the same unsharable event or resource at the same time during communication, so a master party needs to be identified in advance. When a conflict occurs, the slave shall act at the discretion of the master.

Question81: The gatekeeper rejects the access authentication, address resolution request, and gives the resolution result, which of the following signaling can achieve this function

Question82: Which of the following belongs to the extension request (). (3 answers).

Question83: Regarding the Client proxy in the H.460 protocol, the following description is correct ( ).

Question84: Video IVR, on the basis of audio IVR, adds a video interactive interface, which can more easily and intuitively guide users to join a conference or create a conference on the terminal side. ()

Question85: Among the four elements of packet filtering that can generally be omitted by firewalls, the condition is. ( )

Question86: Under static NAT networking, the signaling description of the public network terminal calling the private network terminal is correctly ( ).

Question87: The three modes of operation of the proxy are: Call Stateful, Stateless, transaction Stateful.

Question88: What are some of the following ways to create a video IVR meeting?

Question89: Conversations are uniquely identified by Cal1-ID, From Tag, To Tag, and can be modified after they are created.

Question90: ALG can only be used with certain firewalls.

Question91: What properties does the color rendering index affect on the color of a video image?

Question92: SIP messages fall into two categories, messages and response messages.

Question93: Illuminance, color temperature, white balance and color rendering index, these four indicators of light, have an important impact on the actual image effect of the video conference.

Question94: Dynamic mapping can be from multiple private addresses to a single public address, or from multiple private addresses to multiple public addresses. ()

Question95: GK's call access control function mainly refers to whether to allow nodes to initiate calls based on user rights, network bandwidth and other conditions.

Question96: Regarding the auxiliary IP of high-definition terminals, the following statement is wrong ( )o

Question97: RTP runs on top of ( ) and each RTP message is encapsulated in a ( ) datagram.

Question98: What are the correct items for the following description of the performance of the RSE6500 product?

Question99: The terminal reads the camera data by ( ). (Fill in the blanks)

Question100: H.245 The main signaling consists of ( ). (Select 3 answers).

Question101: The terminal recording request will be sent to the MCU, and then the MCU will uniformly record and broadcast the operation.

Question102: Color temperature affects the reproducibility of the color of the video image, the higher the color temperature, the more color. ( )

Question103: What factors does the quality of digital audio depend on?

Question104:
The frame does not have complete picture data, only data that differs from the previous frame.

Question105: RTP is a real-time transmission control protocol: on a network service of multicast (multicast) or unicast (unicast). Provides end-to-end network transmission capabilities for applications to transmit real-time data such as audio, video or simulation data.

Question106: Users can call the IP address of the MCU, enter the conference lobby, and create a video IVR according to the IVR prompts Of meetings ().

Question107: MP mainly completes which of the following functions. ( )

Question108: Banners and subtitles are transmitted in multicast mode.

Question109: RRQ registers with GK with registration information ( ).

Question110: What addresses are typically included in the RRQ message for the GK registration record address when the node is registered? ( )

Question111: As can be seen from the figure, the venue can not receive remote venue video in the meeting, what measures can the user take to locate the cause of the failure?

Question112: The Call-ID header field serves as a unique identifier for a collection of messages, and in a conversation, the Call-id must be the same in all the last requests sent by each UA. ( )

Question113: Which of the following is not a disadvantage of forward error correction ().

Question114: Three-color lamp refers to the use of red, yellow, blue three color spectrum of the lamp and light emitting lamps, the general luminous color and the color temperature of the lamp has a relationship, with a soft luminous light, uniform brightness, no stroboscopic, high visibility, small power consumption, high voltage resistance, no electric heat disaster characteristics.

Question115: From the logs caught above, it can be seen that which of the following is the cause of the call failure?

Question116: H.460 Signaling interoperability scheme ( ).

Question117: The code flow hole from the public network to the private network is opened by the redirect message of the RTP, through what to maintain? ( )

Question118: The TO tag, the From tag, and the Call-ID together define the peering SIP relationship between UAC and UAS, called a dialog (Dialog)

Question119: Which of the following messages is used for endpoint registration ( ).

Question120: The following description of hd terminals is correct ( ) .

Question121: Incorrect description about recording server (CR101/CR102 ) is ( ).

Question122: The following description of the relationship between the RTCP port number and the RTP port number is correct ().

Question123: A firewall protects a network from attacks by "untrusted" networks, but must also allow legitimate communication between the two networks. ( )

Question124: The conference will not have a terminal when MCU is active and standby.

Question125: For the relationship between the camera and the background, why can't there be too complex background? ( )

Question126: RRJ sendto [ ( 218.5.64.98:18616 )] [5928509444] [[0x00000065:err reg wrong account or passwork]] From the above logs, you can tell that the reason for the failure of registration is ( ).

Question127: Zone management is implemented by which of the following system modules ( ).

Question128: The configuration of the 3G network of hd terminals, the following statement is correct.

Question129: When the terminal enables the remote monitoring function, the user can remotely monitor the main video image or presentation image of the end in the Web interface, and can also take photos to save, but can not view the mainstream image or presentation image of the remote end.

Question130: As can be seen from the figure, the venue can not receive remote venue video in the meeting, what measures can the user take to locate the cause of the failure?

Question131: The final effect of video conferencing is only related to the conference equipment itself, and it is not much related to the integrated environment of various peripherals in the conference room.

Question132: The role of MP is to complete the interaction of control information with the conference TV terminal.

Question133: In the color ring, not only red and green are complementary colors, but everything is included within 90 degrees of the diagonal, such as yellow-green, green, blue-green three Color, both and red constitute a complementary color relationship. ( )

Question134: What are some of the following reasons for the GK side to hang up a call?

Question135: Of the six basic request messages, ( ) are used to query the server capabilities

Question136: The MCU wall-riding mode has its advantages, but there are also certain constraints, such as ( ).

Question137: A high-definition video terminal (referred to as a terminal) is a codec that processes audio and video code streams and data code streams.

Question138: Network recording supports downloading the recording file to the local area in ( ) format, and supports local playback.

Question139: Network Address Translation (NAT) is used to enable translation between private network addresses and public network locations.

Question140: The following description of the advantages and disadvantages of packet loss retransmission ARQ is correct.

Question141: Background tones take complementary colors of skin tones, avoid large areas of skin color proximity or similar colors; Generally use blue, gray, blue-gray combination and other shades; The background image of the large line uses the simplicity and clarity of the picture.

Question142: defines the load head RTP load head structure for the A/B/C3 mode as ( ) mode.

Question143: There are three types of 260.H.264 encoded video frames : ( ).

Question144: Which of the following protocols belongs to the encapsulated transport protocol ( ).

Question145: The core of the NAT mapping is to modify the packet header (source address) to translate the source address into a NAT address ( ).

Question146: Multi-channel cascading, mainly through the establishment of multiple cascaded channels between the cascading conferences of the MCU, the multi-channel code stream on the MCU is sent to the peer MCU.

Question147: The following figure shows the system information for a VP96 Series MCU . From this information, what conclusions can we infer from the following?

Question148: Terminals with built-in mini-McU capabilities can hold multi-point meetings with the built-in MiniMU, but processing power is limited.

Question149: The H460 protocol specifies that the H.323 media streaming portion of the public-private network traversal processing process is

Question150: In the SMC2.0 system, ( ) has the highest level of user rights. (Fill in the blanks)

Question151: Which of the following protocols is used to propagate the stream between the MCU and the network recording server?

Question152: The following description of the standalone SC ride wall networking configuration, which one is wrong?

Question153: Cascade channels are used by priority, and resources are mutually exclusive when at the same priority.

Question154: gateway is a node that provides real-time two-way traffic between the H.323 terminal on the SCN and other nodes on the PBN.

Question155: Network recording and broadcasting does not occupy any resources of the MCU, and there is no interference with the running status of the video conference.

Question156: Which signaling does it mainly include?

Question157: H.460 In the media streaming interconnection scheme, the preservation package is created by which of the protocols listed below ( ).

Question158: Network recording supports downloading recorded files to the local area in the format ( ) and supports local playback. (Fill in the blanks)

Question159: In MCU odd wall mode, you can configure IP routing to specify that IP routes send and receive data through GE1.

Question160: The response message is 3XX for ().

Question161: During point-to-point calls under different GKs, LRQ uses GK routing prefixes to query neighbor GK for information about the called node.

Question162: Desktop tones can be taken as skin color adjacent to color or gray, avoiding the same color of skin tone; Desktop reflectance should be higher than skin tone, highlighting the skin image.

Question163: Color temperature affects the white balance of the camera, and where the color temperature is complex, the image can be cast.

Question164: CANEL transactions can be used for both CANCEL INVITE transactions and CANCEL non-INVITE transactions.

Question165: GK can only be installed on the C or D drive of the operating system.

Question166: Huawei's video product fault location method can be mainly summarized as, grain and grass first, follow the vine to touch the melon, step by step, bold and careful, and pass on the torch. ( )

Question167: When the Huawei video terminal is successfully connected to the camera, the user can set the camera parameters through the web interface of the terminal, such as exposure mode, white balance mode, noise reduction, etc., where the larger the noise reduction value setting, the less noise in the picture and the clearer the details of the image.

Question168: Banners and subtitles are multicast. ()

Question169: During a peer-to-peer number call, the terminal ends up getting the () of the peer terminal from GK and makes the call.

Question170: H.323 The last digit 3 in the protocol represents ().

Question171: In the Huawei Recording solution, administrators can convert on-demand pending and on-demand published AP4 format videos to which of the following formats for users to download?

Question172: HD terminals support ( ) such 16:9 output.

Question173: Which of the following descriptions of SIP registrations is incorrect. ( )

Question174: The key point of signaling packet analysis is to be familiar with the flow of signaling, and when problems are found, focus on which signaling packages should be in the signaling process, and filter irrelevant data. The grab packet didn't catch which messages should have. ( )

Question175: During the MCU main control board backup reversal process, the conference and venue status on the SMC will be offline for about 10 seconds.

Question176: In the Early state, the caller can terminate the dialog by sending (). (2 answers).

Question177: On the terminal web page, you can set parameters for subtitles, which include banners, middle captions, and instant messages. Banners and middle captions can be displayed separately or at the same time; Instant messages can be sent to peer-to-peer private chat, broadcast and sent, or sent at a designated venue.

Question178: In multimedia services, RTP is used for real-time datagram transmission and RTCP is used to detect the quality of service for an RTP session.

Question179: 53.H.460 Networking, the RTP keep alive stream is ( ).

Question180: HD terminals support peer-to-peer ( ) calls.

Question181: Full HD image resolution is. ( )

Question182: Wireshark is a network packet analysis tool whose main role is to capture network packets in real time on the interface and display the detailed protocol information of the packets in detail. ( )

Question183: Header domains carry the properties of SIP entities, message bodies, and so on.

Question184: Which of the following signalings is not an H.245 signaling. ( )

Question185: Which of the following features does the gatekeeper provide (3 answers).

Question186: To use NLOG properly, the FLASH plug-in must be installed or it cannot be used.

Question187: In the Cseq header domain, Cseq is used to uniquely identify an invitation or a registration. ( )

Question188: As shown in the figure, the RTCP instance flow includes SR, RR, and ( ) messages.

Question189: Banners are used to briefly display meeting content, and subtitles are used to highlight the meeting topic.

Question190: The veneer slot information of the VP9660 is shown in the following:

Question191: The SIP protocol is an application-layer protocol.

Question192: The gatekeeper's address translation function refers to the conversion of farm names or numbers to IP addresses based on the data table at the time of node registration.

Question193: Cascading between MiniMCU, the default caller will be the primary MCU and the MiniMC that is already the primary MCU will be called It will not be changed again during the meeting. ( )

Question194: What are the ways to schedule recorded meetings. ( )

Question195: The basic functions of the firewall include: content filtering, user authentication, VPN, Application Proxy, NAT, packet filtering & state detection, IDS and alarms, logs, etc.

Question196: The chromatic aberration (YPbPr) output supports both 16:9 and 4:3

Question197: Each RTP datagram consists of two parts, the header and the payload, where the meaning of the first 12 bytes of the header is fixed , and the payload can be audio or video data.

Question198: The signal stream of the audio self-ring is. ( )

Question199: Under the static NAT networking, the packet of the private network terminal through the firewall will change, and the following description is wrong ( ).

Question200: The INFORMATION that the IP header in the SETUP message does not contain Is there? ( )

Question201: Cascade channel usage rules are consumed by priority, and resources are mutually exclusive when at the same priority.

Question202: If both the sender and receiver () are the same, the MCU forwards directly. (3 answers).

Question203: In the Cilent/Server model, the primary function of request proxy server is to decide where to send signaling messages.

Question204: The primary purpose of 515.H.323 is to establish peer-to-peer media sessions and multipoint media conferences. ()

Question205: When an endpoint/MCU calls with a number, the ARQ call information does not include the following () of the following

Question206: Packet capture of network data streams can be mainly achieved in the following ways. ( )

Question207: Direct sound refers to the sound signal that reaches the listener directly from the sound source, and the meeting requirements are mainly direct sound.

Question208: networking network, the H.245TCP connection of the private network terminal is established with TS. ()

Question209: H.323 defines the H.323 Gateway GateKeeper, Multipoint Processor (MP), but does not define the Multipoint Conferencing Control Unit (MCU).

Question210: The Clear Fluency Strategy works with the H.264H.265 protocol, and if there is no ability in the public capability, the Clear Fluency Strategy will not work. ()

Question211: In the SMC2.0 system, which of the following user rights has the highest level.

Question212: The response message "lxx" indicates . ( )

Question213: In video conferencing, local noise is required not to be greater than ().

Question214: Common SIP calls to the SDP negotiation process include ( ).

Question215: A meeting can support up to ( ) group multi-screen. (Fill in the blanks)