1K0-001 · Question #325
Which of the following best describes 64,000 bits per second?
The correct answer is C. DS0. See the full explanation below for the reasoning.
Question
Which of the following best describes 64,000 bits per second?
Options
- ADS1
- BDS3
- CDS0
- DCEPT1
How the community answered
(30 responses)- A17% (5)
- B7% (2)
- C73% (22)
- D3% (1)
Community Discussion
10
Ingrid P.Nov 10, 2025C is the correct answer. DS0 is the foundational 64 Kbps channel in the digital signal hierarchy, and that number deserves its own card because every other DS level builds on it multiplicatively. DS1 bundles 24 DS0 channels to hit 1.544 Mbps, and DS3 stacks 28 DS1s to reach 44.736 Mbps, so if you blank on DS1 or DS3 during the exam you can reconstruct them from the DS0 anchor. CEPT1 (E1) is the European equivalent at 2.048 Mbps, which uses 32 channels at 64 Kbps each, so again DS0 is the common thread. I keep a card with one side reading "single digitized voice channel" and the other reading "DS0, 64 Kbps" because that pairing shows up across multiple exam objectives and the interval resets are short until it sticks.
Dervla O.Nov 10, 2025The 24 DS0 count for DS1 is worth drilling separately too, because exams love asking you to calculate the DS1 rate from scratch and students who memorized the 1.544 number cold often stumble when the stem flips the question and gives you channels instead.
Yusuf A.Oct 31, 2025Yep, C is right, DS0 is a single 64 Kbps channel, which is actually the base building block that 24 of them get multiplexed together to form a DS1. My senior had me remember it this way: DS0 is the "atom" of the TDM hierarchy, everything above it is just multiples.
Toby R.Nov 3, 2025Solid analogy, and worth noting the 64 Kbps figure comes from 8 bits sampled 8000 times per second, which is the math behind why voice calls landed at that rate in the first place.
Toby R.Oct 25, 2025DS3 runs at 44.736 Mbps which breaks down into those 64 Kbps building blocks at the channel level, so when the question references 64,000 bits per second it is pointing to the base rate that DS3 aggregates, making B the logical choice here. I went with B on this one and felt good about it walking out.
Yusuf A.Oct 26, 2025Hey Toby, you actually described DS0 perfectly there, the 64 Kbps channel is DS0, which is answer C, not DS3 which is what B points to. DS3 is way up the hierarchy at 44.736 Mbps, so the question is asking about the base channel itself.
Luis F.Nov 8, 2025Guys I keep coming back to B, DS3, because when you think about the sheer scale of digital signal hierarchy it just feels like 64K fits right in that high-throughput tier that DS3 represents. I know some people here are saying C but I am telling you, DS3 is where the real bandwidth action happens and 64Kbps lines right up with it in my head from the study guide I read last week.
Ingrid P.Nov 9, 2025Luis, C is correct here because 64 Kbps is the DS0 rate, the single-channel baseline of the digital signal hierarchy, while DS3 runs at roughly 44.736 Mbps, which is orders of magnitude higher. That DS0 equals 64 Kbps is worth a dedicated card since it anchors the whole DS hierarchy math.
Dervla O.Nov 21, 2025Going with A on this one, DS1 runs at 64 Kbps and that maps directly to 64,000 bits per second, so the stem is practically spelling it out for you. I re-read it twice and nothing in the wording points me anywhere else.
Yusuf A.Nov 21, 2025Hey Dervla, actually my mentor drilled this into me, 64 Kbps is a single DS0 channel, and DS1 bundles 24 of those together with framing bits to land at 1.544 Mbps, which is why C is the one they're looking for here.