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Câu trả lời yêu thích35%
Câu trả lời143
  • T1 line? Totally confused.?

    I understand the logical part of T1 in how is splits data into channels that are 64 kbs wide (B-channels), but I'm totally confused as to the physical aspect of a T1.

    Does it use the public telephone network or does it use a proprietary cable (copper or fiber) circuit between the subscriber the switching office? If it doesn't use POTS, then why am I reading that ISDN PRI is basically the same thing as a T1? Isn't ISDN designed to transmit digital data over POTS lines?

    Banging my head against a wall here. lol

    1 Câu trả lờiComputer Networking9 năm trước
  • Difference between static typing and dynamic typing?

    I get that one is checked at compile time and the other is checked at run time, but what does this imply?

    That types are predefined for the programmer in one and has to be declared in the other? Can someone give me a dummy, n00b, conceptual definition for the difference between the two in regards to data types?

    1 Câu trả lờiProgramming & Design9 năm trước
  • Difference between tunneling and encapsulation?

    I don't think I quite understand the difference between the two. Encapsulation is what protocol suites do to make each layer modular, where each layer adds its own control header or trailer to the protocol data unit. Tunneling is encapsulating one protocol within another for the purpose of secure transmission or delivering mismatched protocols (like toledo for IPv6 in an IPv4 network?). Does this sound right? And if so, wouldn't tunneling just be a type of encapsulation? Is there really any difference BIG difference between the two words except purpose and little things like encryption?

    2 Câu trả lờiComputer Networking9 năm trước
  • Logical topology of a Wireless LAN?

    I get that the WAP takes the place of a switch/hub in creating a physical star, but what kind of logical topology should I think of with wireless?

    1 Câu trả lờiComputer Networking9 năm trước
  • Need help with this polynomial?

    3x^4+5x^3-2x^2

    Okay, this is part of my study material for my precalc midterm tomorrow.

    Basically, what my professor is asking is to find all possible rational zeroes, find all real zeroes, find the x intercept, find the y intercept, and find the end behavior.

    What I understand so far is the y intercept (hur duhhr), and the end behavior, but I feel totally lost in all the other aspects. The only tool I know of to find possible zeroes is the rational roots tests, but how the $%# does that work when the constant coefficient is essentially zero? Also, how do I factor? I know if the polynomial is ^3 leading term, I can use one of the zeroes with synthetic division to reduce the equation to a quadratic and factor out the other zeroes from there, but this just leaves me confused.

    2 Câu trả lờiMathematics9 năm trước
  • CompTIA Network+ Practice Test Question, stuck! Help?

    You are configuring network addresses for your local intranet. The addresses are based on the following network address:

    190.1.164.0/22

    You need to configure the following subnetworks:

    Network A - 300 hosts

    Network B - 200 hosts

    Network C - 60 hosts

    Network D - 40 hosts

    You want to keep the unused addresses in each subnetwork to a minimum.

    Which configuration should you use

    Network A - 190.1.164.0/23

    Network B - 190.1.166.0/24

    Network C - 190.1.167.128/26

    Network D - 190.1.167.64/26

    Network A - 190.1.164.0/23

    Network B - 190.1.164.0/24

    Network C - 190.1.166.128/26

    Network D - 190.1.166.64/26

    Network A - 190.1.164.0/22

    Network B - 190.1.166.0/23

    Network C - 190.1.167.128/26

    Network D - 190.1.167.64/26

    Network A - 190.1.164.0/23

    Network B - 190.1.166.0/24

    Network C - 190.1.167.128/26

    Network D - 190.1.167.64/27

    More important than the answer, I need to understand how they're arriving at this conclusion? I'm pretty sure the answer is the first configuration, but I'm totally brainfarting as to how to get there. I get how to figure out the proper # of hosts by simply taking the answers and subtracting the notation size from 256, but how did they come up with the new network addresses?

    2 Câu trả lờiComputer Networking9 năm trước
  • Logical topology using a switch?

    I think I get that a Hub and WAP continue to use logical bus topologies because every device shares the same bandwidth and adheres to CSMA/CD, but how would I think of the logical topology of a network employing a switch? Would it be point-to-point? Or should I still think of it as a logical bus that has point-to-point features using ASICs to map out the MAC address/port relation?

    1 Câu trả lờiComputer Networking9 năm trước
  • Decolorizing Agent in Gram Stain?

    Is it really important to use 95% alcohol or can I use 70% to 90% with similar to duplicate results?

    3 Câu trả lờiBiology10 năm trước
  • 2sin(theta)= 1 - 2cos(theta)?

    Solve for theta, restricting the domain to 0 to 360.

    4 Câu trả lờiMathematics1 thập kỷ trước
  • csc^ * x/2 = 2secx??

    I don't understand how to solve this question. I am unsure how to even start this problem let alone finish it. I need two angles within 0 to 360, and more importantly, I need to understand HOW to do this.

    1 Câu trả lờiMathematics1 thập kỷ trước
  • Solving Trig Identities (w/ fractions, poss. work on both sides)?

    Okay, I'm lost and frustrated at this point. I seem to be one, inspiration, or step away from solving these type of equations, but it eludes me. The simpler ones, no prob, but when it comes to the following equations, I am foooked:

    (-1/[tan - sec) + (-1[tan + sec]) = 2tan

    (tan/[1 + cos]) + (sin[1- cos] = cot + sec*csc

    (1 - sin)/(1 + sin) = sec^2 - 2sec*tan + tan^

    If you know the answer, can you please, pleaseeeee show me all the steps and give me a little outline on your method? I need to see what steps I am not doing correctly or at all.

    1 Câu trả lờiMathematics1 thập kỷ trước
  • Is a G-Protein considered a second messenger?

    So the neurotransmitter binds to the g-protein coupled receptor site, which, long story short, changes the GPCR and activates a G-Protein on the intracellular side, causing a cascade that leads to blah blah blah blah. That would make the neurotransmitter a ligand and the G-Protein a second messenger. Am I understanding this correctly?

    3 Câu trả lờiBiology1 thập kỷ trước
  • derivative of an equation?

    I've got a pretty good grasp on the subject so far, but I'm still confused about some minor details and while the details may be stupid to some, I still want to confirm to make sure I'm not on the wrong yellow brick road.

    When you don't plug in anything for x using the difference quotient, whatever solution you get lets you plug in any x point on the line for that equation to find its deriv. right? like the d for for 5x^ -3x-7 gives me a general solution of 10x-3, so can I then just start plugging in points now? Like for x=3 of the above equation, the derivative is 27 right?

    1 Câu trả lờiMathematics1 thập kỷ trước