Redes Fórmulas

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      "### Aloha\n",
      "\n",
      "$t_m$: Tiempo de marco de longitud fija\n",
      "\n",
      "$P(k)$: Probabilidad de $k$ intentos de transmisi\u00f3n sobre $tm$ (retx de viejos y nuevos) es de tipo Poisson, con media $G$ [intentos de $tx/tm$].\n",
      "\n",
      "$$ P(k) = \\dfrac{G^k*e^{-g}}{k!} $$\n",
      "\n",
      "$P_0$: Probabilidad de que una trama no sufra colisi\u00f3n.\n",
      "\n",
      "$$ P_0 = e^{-g} * e^{-g} = e^{-2g} $$\n",
      "\n",
      "$$ \\text{ ya que } $$\n",
      "\n",
      "$$ t_\\text{vulnerable} = 2t_m $$\n",
      "\n",
      "$S$: Tramas transmitidas efectivamente por tiempo de marco [$\\text{tramas}/t_m$]\n",
      "\n",
      "$$ S = G * P_0 $$\n",
      "\n",
      "$$ S = G * e^{-2g} $$\n",
      "\n",
      "$$ S_{max | G=0.5} = \\dfrac{1}{2e} \\approx 0.184 $$\n",
      "\n",
      "M\u00e1ximo uso del canal del $18.4\\%$\n",
      "\n",
      "### Aloha Ranurado\n",
      "\n",
      "$$ t_\\text{vulnerable} = t_m $$\n",
      "\n",
      "$$ P_0 = e^{-g} $$\n",
      "\n",
      "$$ S = G * e^{-g} $$\n",
      "\n",
      "$$ S_{max | G=1} = \\dfrac{1}{e} \\approx 0.368 $$\n",
      "\n",
      "M\u00e1ximo uso del canal del $36.8\\%$\n",
      "\n",
      "### CSMA/CD\n",
      "\n",
      "M\u00ednimo tiempo de trama = $ 2 \\tau $\n",
      "\n",
      "### Token Ring\n",
      "\n",
      "$$ L_{\\text{max}|\\text{trama}} = T_{\\text{token}} * Rb $$\n",
      "\n",
      "$$ T_{\\text{max}|\\text{token}} = v_{\\text{propagaci\u00f3n}} * L_{\\text{anillo}} $$\n",
      "\n",
      "### C\u00e1lculo de RTT (Jacobson)\n",
      "\n",
      "$$ RTT_i = \\alpha RTT_{i-1} + (1 - \\alpha) * M_i $$\n",
      "\n",
      "$$ RTO_i = RTT_i + 4D_i $$\n",
      "\n",
      "$$ D_i = \\alpha * D_{i-1} + (1 - \\alpha) * | RTT_{i-1} - M_i | $$"
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      "def rti(a, rti, mi):\n",
      "    return a * rti + (1-a) * mi\n",
      "\n",
      "def d(a, di, rti, mi):\n",
      "    return a * di + (1 - a) * abs(rti - mi)\n",
      "\n",
      "def rto(rti, di):\n",
      "    return rti + 4*di\n",
      "    \n",
      "rto(42.34, 3.59375)"
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