TMP Technologies & Infrastructure 5 — Questions and Answers
Question 1: What is the primary purpose of a Diameter protocol in LTE/4G networks?
- To carry voice calls over IP between eNodeBs
- To provide AAA (Authentication, Authorization, and Accounting) signaling in the EPC, replacing SS7 RADIUS (Correct answer)
- To manage handover procedures between base stations
- To allocate frequency bands for uplink and downlink
Correct answer: To provide AAA (Authentication, Authorization, and Accounting) signaling in the EPC, replacing SS7 RADIUS
Diameter is the IETF successor to RADIUS used in LTE/4G for AAA services and policy control, replacing SS7-based protocols in the Evolved Packet Core.
Question 2: In a multi-tenant data center, what does a 'cross-connect' service provide?
- A managed firewall between tenant VLANs
- A direct physical or logical connection between two tenants or a tenant and a carrier without traversing the public internet (Correct answer)
- Shared bandwidth pooling across all tenants in a cabinet
- Remote hands support for equipment installation
Correct answer: A direct physical or logical connection between two tenants or a tenant and a carrier without traversing the public internet
A cross-connect is a dedicated circuit within the data center facility connecting two parties directly, enabling private low-latency interconnection without internet exposure.
Question 3: Which ITU-T standard family defines the Optical Transport Network (OTN) digital wrapper hierarchy?
- G.711
- G.803
- G.709 (Correct answer)
- G.652
Correct answer: G.709
ITU-T G.709 defines the OTN framing structure, including the Optical Channel Data Unit (ODU) hierarchy and the digital wrapper that adds FEC and overhead to client signals.
Question 4: A telecom engineer is configuring QoS on a carrier router. What is the purpose of Traffic Policing versus Traffic Shaping?
- Policing buffers excess traffic; Shaping drops excess traffic immediately
- Policing drops or marks excess traffic immediately; Shaping buffers excess traffic to smooth output rate (Correct answer)
- Both techniques achieve identical results through different hardware
- Shaping applies only to voice traffic; Policing applies to data traffic
Correct answer: Policing drops or marks excess traffic immediately; Shaping buffers excess traffic to smooth output rate
Traffic policing enforces a rate limit by dropping or re-marking packets that exceed the defined rate, while shaping queues excess packets to transmit them within the allowed rate.
Question 5: What is the key difference between TDM (Time Division Multiplexing) and statistical multiplexing used in packet networks?
- TDM allocates fixed time slots to each channel regardless of activity; statistical multiplexing allocates bandwidth dynamically based on actual traffic (Correct answer)
- TDM is used only for video; statistical multiplexing is for voice
- Statistical multiplexing guarantees fixed latency; TDM does not
- TDM requires more bandwidth than statistical multiplexing for the same number of users
Correct answer: TDM allocates fixed time slots to each channel regardless of activity; statistical multiplexing allocates bandwidth dynamically based on actual traffic
TDM reserves dedicated time slots per circuit whether or not data is being sent, while statistical multiplexing shares capacity among users dynamically, improving efficiency when traffic is bursty.
Question 6: In a cellular network, what does the term 'spectrum refarming' refer to?
- Purchasing new spectrum at government auction
- Reallocating existing licensed spectrum from an older technology (e.g., 2G) to a newer one (e.g., 4G/5G) (Correct answer)
- Sharing spectrum between two competing operators via a neutral host
- Dividing spectrum into smaller channels to reduce interference
Correct answer: Reallocating existing licensed spectrum from an older technology (e.g., 2G) to a newer one (e.g., 4G/5G)
Spectrum refarming is the process of repurposing frequencies already licensed to an operator from legacy technologies to more spectrally efficient modern standards.
Question 7: Which feature of MPLS Traffic Engineering (MPLS-TE) allows a path to be pre-established so traffic can switch immediately upon primary path failure?
- Fast Reroute (FRR) (Correct answer)
- Load Balancing via ECMP
- Penultimate Hop Popping (PHP)
- Label Stacking
Correct answer: Fast Reroute (FRR)
MPLS-TE Fast Reroute pre-computes and pre-signals backup LSPs so that traffic can be redirected in sub-50ms upon detecting a link or node failure.
TMP Technologies & Infrastructure 5
What is the primary purpose of a Diameter protocol in LTE/4G networks?