Predictika · Arista Etherlink AI back-end fabric
An AI sales or design agent proposes an AI back-end fabric order: 7060X6, 7800R4 or 7700R4 switches with the optics, cables and software release they need. Before it goes out, the agent sends the order to Predictika, which checks ports, optics, cabling, minimum software and the figures the order states against a declarative model of Arista's published rules, and returns a verdict, every reason, and the figures it computed. This validator produces no price build-up: Arista does not publish prices, and none are used.
Source and independence. The rules in this validator come from Arista's public documents: the Transceiver Compatibility and Interoperability guide, the 7060X6 Series, 7800R4 Series AI Spine and 7700R4 Distributed Etherlink Switch datasheets, the 400G Transceivers and Cables FAQ, and the Arista and Broadcom AI Networking Deployment Guide. Arista is not involved in this demonstration and has not endorsed it. The customer, Harbor Point Research, is fictional. Quantities, link lengths, connector and fiber types, the site's ambient temperature, the EOS release and the figures an order states are supplied by the customer's own design, not by Arista.
This validator handles any order for these Arista switches and their optics and cables — not just the scenarios shown below.
Not covered: prices, lead times, discounts and support terms (Arista publishes none), other Arista series, and fiber plant design beyond connector type, fiber type and length. Where Arista's own documents disagree, the validator does not guess: it sends the order to a person for approval. This applies to the longest passive copper run (3, 4 or 5 m depending on the document), to linear pluggable optics on switches that one document lists and another does not, and to mixing line-card variants in a chassis. Where Arista has not published a minimum EOS release for a switch, the validator says so in a note and checks only the optic and cable minimums.
8 scenarios in 3 groups · each group runs from the agent’s first attempt to the outcome · click one to switch
Illustrative agent statement. The validator receives the structured request below.
Proposing agent: AI sales agent (scripted)
Before sending, the agent must call Recorded run
What this means
Our assessment of what a typical rules-based CPQ (product rules, price rules and validation rules, as in Salesforce CPQ) does with the same cases. It is a judgment about effort and reliability, not a claim that nothing can be built.
| What the validator caught | Typical rules-based CPQ | Predictika |
|---|---|---|
| Stated ports and bandwidth that differ from what the order actually contains | Only with workarounds The stated figures are rarely fields on the order. Ports and Tbps have to be summed from every switch and link group and compared by a custom rule. | The stated figures travel with the order and are compared with the computed ones on every call. |
| An optic that needs angled connectors, installed through flat patch panels | Only with care A compatibility rule between optic and connector. It works if the connector type is captured on the order and the table is kept current. | Optic, connector, fiber type and reach are checked together from one table. |
| A minimum EOS release that depends on the optic and, separately, on the switch | Only with care Product rules per optic and per switch, fired as each item is picked, so the second release requirement shows up only after the first is fixed. | Every release requirement is checked together against the one release on the order. |
| ZR and ZR+ limits that depend on the switch: ports allowed and site temperature | Only with workarounds Per-switch port limits and an environmental condition that is not usually a field in a quote. | The count and the site temperature are compared with the switch's limits in the same call. |
| A chassis whose ports come from line cards, against the port count ordered | Only with care A capacity rule per chassis and line-card count. Reliable when the line-card quantity is always entered. | Chassis capacity, line-card ports and fabric modules are checked together. |
| Two Arista documents that disagree, such as the longest passive copper run | Only with workarounds A rule has to pick one number. Routing the disagreement to a person needs a separate approval path. | The agreed part is enforced and the disputed part becomes a needs-approval finding with the reason. |
Every rule is checked on every call, in any order the choices arrive; one problem never hides another. Blocking findings stop the order; approval findings need a person to sign off; everything else is computed. These are the findings the 36 test cases produced.
| 1 | Stated host-facing ports 1,280; the validator computes 1,152. |
| 2 | Stated host-facing bandwidth 1,024 Tbps; the validator computes 921.6 Tbps. |
| 3 | Fabric-facing links: OSFP-800G-ZRP needs EOS 4.36.0 or later; the order runs EOS 4.35.2. |
| 4 | Fabric-facing links: DCS-7060X6-64PE supports 800G-ZR/ZR+ on at most 32 ports; the order asks for 64. |
| 5 | Host-facing links: OSFP-800G-2VSR4 needs angled (APC) MPO connectors, but the patch panels are UPC. |
| 6 | Host-facing links: OSFP-800G-2VSR4 reaches 50 m; the link is 70 m. |
| 7 | DCS-7804R4 has 144 OSFP ports in all; the order asks for 200 on each switch. |
| 8 | Host-facing links: passive copper at 4 m. Arista documents give different limits for passive copper (3 m in the 400G optics FAQ, 4 m in the 7700R4 datasheet, 5 m in the AI networking deployment guide); a person must confirm. |
| 9 | Host-facing links: the Arista transceiver guide (Table 2.1) does not list DCS-7060X6-32PE for linear pluggable optics, while its datasheet describes LPO support; a person must confirm before LPO-800G-2DR4 is ordered. |
| 10 | Host-facing links: LPO-800G-DR8 needs EOS 4.36.0 or later; the order runs EOS 4.35.2. |
| 11 | Host-facing links: QDD-800G-2FR4 is a QSFP-DD module and does not fit the OSFP ports of DCS-7060X6-64PE. |
| 12 | Host-facing links: OSFP-800G-2LR4 uses LC duplex connectors, but the cabling is angled MPO (APC). |
| 13 | Host-facing links: OSFP-800G-2XDR4 runs on single-mode fiber, but the plant is MMF. |
| 14 | Fabric-facing links: 800G-ZR and ZR+ optics are listed only for the 7060X6-64PE, the 7800R4 line cards and the 7280R4-32PE; DCS-7060X6-32PE is not listed. |
| 15 | Fabric-facing links: 800G-ZR/ZR+ on DCS-7060X6-64PE needs an ambient temperature of 30 C or lower; the site is 35 C. |
| 16 | Each leaf has 20 fabric ports (40 links when each port splits into two 400G links); they cannot be spread evenly over 15 spines. |
| 17 | 8 spines is not one of the 10, 20 or 40 spine designs in the 7700R4 datasheet. |
| 18 | 70 leaves over 10 spines need 140 ports on each spine; a 7720R4-128PE spine has 128. |
| 19 | Spines connect only to leaves; spine-to-spine links are not permitted. |
| 20 | DCS-7700R4C-38PE has 38 OSFP ports in all; the order asks for 40 on each switch. |
| 21 | DCS-7700R4C-38PE has 18 host-facing ports on each leaf; the order asks for 20. |
| 22 | The order has 4 fabric modules; the datasheet lists a fabric module as required in each of fabric slots 1 to 5. |
| 23 | The chassis mixes line-card variants; the datasheet does not state rules for mixing the 7800R4C, 7800R4 and 7800R4K line cards. |
| 24 | A 400G-DR4 module and a 400G-FR4 module are not interoperable (listed as N/A in Table 24 of the transceiver guide). |
| 25 | DCS-7060X6-32PE needs EOS 4.34.2 or later; the order runs EOS 4.33.0. |
| 26 | Host-facing links: A-O800-O800-xM reaches 30 m; the link is 40 m. |
| 27 | Host-facing links: C-O800-O800-1M is listed only in lengths up to 1 m; the run is 2 m. |
| 28 | 5 line cards at 36 ports each cannot supply the 200 ports the order asks for on each chassis. |
| 29 | Host-facing links: C-O800-2Q400-xM is listed only in lengths up to 4 m; the run is 6 m. |
| 30 | Host-facing links: LPO-800G-DR8 needs angled (APC) MPO connectors, but the patch panels are UPC. |
| 31 | Host-facing links: LPO-800G-DR8 runs on single-mode fiber, but the plant is MMF. |
| 32 | Fabric-facing links: DCS-7060X6-64PE supports 800G-ZR/ZR+ on at most 32 ports; the order asks for 48. |
The recorded result of the validator for each scenario on this page: the request the AI agent sent, the verdict, and every finding, in the order they appear above.
The agent's request. Please order the campus interconnect links for Harbor Point Research: 2 DCS-7060X6-64PE switches on EOS 4.35.2. Each has 48 ports of OSFP-800G-ZRP long-haul optics and 16 host-facing ports of LPO-800G-DR8 optics over 30 m of multimode fiber through patch panels with flat (UPC) MPO connectors. The site ambient temperature is 30 C. The order states 128 800G ports and 102.4 Tbps in all. It is ready to send.
Verdict: Blocked.
The agent's request. Please order the campus interconnect links for Harbor Point Research: 2 DCS-7060X6-64PE switches on EOS 4.36.0. Each has 32 ports of OSFP-800G-ZRP long-haul optics and 32 host-facing ports of LPO-800G-DR8 optics over 30 m of single-mode fiber through patch panels with flat (UPC) MPO connectors. The site ambient temperature is 30 C. The order states 128 800G ports and 102.4 Tbps in all. It is ready to send.
Verdict: Blocked.
The agent's request. Please order the campus interconnect links for Harbor Point Research: 2 DCS-7060X6-64PE switches on EOS 4.36.0. Each has 32 ports of OSFP-800G-ZRP long-haul optics and 32 host-facing ports of LPO-800G-DR8 optics over 30 m of single-mode fiber with angled MPO connectors. The site ambient temperature is 30 C. The order states 128 800G ports and 102.4 Tbps in all. It is ready to send.
Verdict: Allowed.
The agent's request. Please order the AI back-end fabric for Harbor Point Research: 64 DCS-7700R4C-38PE leaf switches and 10 spine switches, all on EOS 4.36.0. Each leaf has 18 host-facing ports on 1 m passive 800G copper cables and 20 fabric-facing ports on OSFP-800G-2XDR4 optics over 150 m of single-mode fiber with angled MPO connectors. The order states 1,280 host-facing 800G ports and 1,024 Tbps of host-facing bandwidth. It is ready to send.
Verdict: Blocked.
The agent's request. Please order the AI back-end fabric for Harbor Point Research: 64 DCS-7700R4C-38PE leaf switches and 10 spine switches, all on EOS 4.36.0. Each leaf has 18 host-facing ports on 1 m passive 800G copper cables and 20 fabric-facing ports on OSFP-800G-2XDR4 optics over 150 m of single-mode fiber with angled MPO connectors. The order states 1,152 host-facing 800G ports and 921.6 Tbps of host-facing bandwidth. It is ready to send.
Verdict: Allowed.
The agent's request. Please order the aggregation chassis for Harbor Point Research: one DCS-7804R4 with 4 line cards on EOS 4.36.0, with 200 host-facing 800G ports on C-O800-2Q400 passive copper breakout cables, 4 m long. The order states 200 host-facing 800G ports and 160 Tbps of host-facing bandwidth. It is ready to send.
Verdict: Blocked.
The agent's request. Please order the aggregation chassis for Harbor Point Research: one DCS-7808R4 with 6 line cards on EOS 4.36.0, with 200 host-facing 800G ports on C-O800-2Q400 passive copper breakout cables, 4 m long. The order states 200 host-facing 800G ports and 160 Tbps of host-facing bandwidth. It is ready to send.
Verdict: Needs approval.
The agent's request. Please order the aggregation chassis for Harbor Point Research: one DCS-7808R4 with 6 line cards on EOS 4.36.0, with 200 host-facing 800G ports on C-O800-2Q400 passive copper breakout cables, 2 m long. The order states 200 host-facing 800G ports and 160 Tbps of host-facing bandwidth. It is ready to send.
Verdict: Allowed.
The text of the narrated walkthrough, step by step.