A Framework of Intelligence Delivery Network (IDN) for Deep Learning Inference

2.1. AI Inference Workload Characteristics

AI inference workloads differ from traditional web services and from model training workloads in several ways.¶

First, many inference requests are interactive and latency-sensitive. A user-facing assistant, a real-time translation system, or a perception pipeline may be sensitive to time-to-first-token, time-per-output-token, tail latency, and service degradation under overload. This differs from batch-oriented training and from many static content-delivery workloads.¶

Second, inference workloads are geographically and organizationally distributed. Demand may be concentrated in particular regions, access networks, enterprises, campuses, or application communities. These demand patterns can change quickly as applications, events, and user behavior change.¶

Third, inference frequently operates on user-generated, enterprise, or sensor data. Such data may be sensitive, regulated, or subject to locality constraints. Moving all input data to remote data centers can increase wide-area traffic and may create privacy, governance, or compliance concerns.¶

Fourth, inference workloads are heterogeneous. Different tasks require different tradeoffs among quality, latency, model size, cost, and privacy. A single AI service may include simple tasks that can be served by a compact model variant and complex tasks that require a larger or more capable model. Similar heterogeneity has been observed in distributed inference and mobile vision systems [Elf].¶

2.2. Limitations of Cloud-Centric Serving

Centralized cloud infrastructure plays an important role in AI inference because it provides abundant computing resources and can host the largest models. However, relying solely on a cloud-centric deployment model introduces several limitations.¶

Routing all requests to a limited set of data centers can increase end-to-end latency and wide-area traffic. Centralized serving can also create resource contention and queueing delay during demand bursts. Because AI inference consumes accelerator time and memory per request, it cannot be scaled in exactly the same way as delivery of static bytes from cache.¶

Cloud-centric serving can also make poor use of distributed compute resources. Regional sites, edge servers, customer-premise environments, and local devices may be able to execute selected capability variants or reusable stages of a workflow, but they need to be admitted, described, monitored, and selected safely. Without a common architectural view, those resources are difficult to use as part of a coherent inference service.¶

Finally, centralized serving can be misaligned with policy constraints. A request involving private or regulated data may need local execution, stronger isolation, tenant-specific controls, or processing within a jurisdiction. IDN treats such constraints as part of service placement and routing.¶

2.3. Intelligence Delivery Versus Content Delivery

IDN is inspired by CDNs, but intelligence is harder to deliver than content. A content object is commonly a stable byte sequence that can be cached and validated with relatively well-understood HTTP caching mechanisms [RFC9111]. CDN request routing selects an appropriate serving location using mechanisms such as DNS redirection, anycast, HTTP redirection, or combinations of these methods [RFC3568].¶

An AI service may depend on a base model, adapters, tokenization logic, safety filters, retrieval indexes, runtime packages, tool integrations, and reusable inference state such as prompt prefixes, activations, or key-value (KV) caches. These elements have compatibility constraints, hardware requirements, loading costs, sharing restrictions, and policy implications. The selected service instance is therefore not necessarily the geographically closest node. It is the node, service instance, or execution plan that best satisfies capability, quality, state, load, network, and policy constraints.¶

This distinction motivates a capability-centric and state-aware architecture. IDN needs a common way to describe what intelligence is requested, what capabilities exist, what resources can execute them, what reusable state exists, how state may be shared, and which trust and policy constraints apply.¶

2.4. Architectural Challenges

IDN is motivated by the following architectural challenges:¶

• Capability abstraction: AI capability needs to be represented at a granularity that is more flexible than whole-model replication but still stable and meaningful as a service object.¶

• Compute resource integration: Heterogeneous compute nodes need to advertise resource profiles, dynamic state, locality, supported runtimes, and trust evidence in a scalable manner.¶

• Demand-driven deployment: Capability variants need to be deployed, activated, scaled, migrated, or withdrawn according to demand locality, resource cost, and policy constraints.¶

• Capability-aware service routing: Requests need to be steered to suitable service instances or multi-stage execution plans based on capability, quality, state affinity, network conditions, compute load, and policy.¶

• State-aware caching and reuse: Model artifacts, prompt prefixes, tensor state, and results may be reusable, but their correctness, compatibility, mobility, and privacy properties differ.¶

• Trust management: A distributed inference path needs mechanisms for model provenance, object authentication, node identity, delegation, policy verification, and auditability.¶

3.1. Design Principles

The IDN framework is guided by the following design principles:¶

• Capability-centric delivery: Intelligence is represented as bounded inference capabilities that can be described, placed, discovered, selected, and executed independently of a single physical model checkpoint.¶

• Provider-controlled hierarchical deployment: The deployment assumes a provider-managed serving hierarchy spanning cloud, regional, edge, and local resources. The provider retains control of IDN-specific functions such as placement, request routing, caching, trust management, policy enforcement, and updates.¶

• CATS-compatible steering: IDN service routing is aligned with CATS concepts. An IDN service may have multiple service instances, and steering decisions need to account for both network and compute conditions.¶

• State-aware operation: Reusable model artifacts and inference state are treated as named, managed objects whose location, compatibility, sharing scope, and migration cost affect routing and caching decisions.¶

• Policy and trust as first-class constraints: Privacy, locality, isolation, provenance, attestation, and delegation constraints influence deployment and routing decisions.¶

• Incremental evolution: IDN is intended to evolve through prototypes, provider-domain deployments, and later standardization of common descriptors and interfaces.¶

3.2. System Model and Deployment Assumptions

IDN assumes a large-scale AI service environment operated by a single AI provider, i.e., a single provider-controlled administrative domain. This assumption is analogous to existing CDN deployments, i.e., infrastructure may be physically hosted in enterprise, campus, or customer-premise environments, but the service provider controls application-level functions such as service software, request steering, cache policy, updates, monitoring, and safety policy.¶

The resource hierarchy contains four classes of resources:¶

• Cloud nodes: centralized data centers or cloud regions that host the largest foundation models, maintain the most complete capability set, and provide abundant compute, memory, and storage.¶

• Regional nodes: regional PoPs, metro-scale data centers, or interconnection sites that aggregate demand across a large geographic area or access network. They can host frequently used capabilities with lower latency than centralized cloud data centers.¶

• Edge nodes: access-network PoPs, ISP-side cache clusters, MEC sites, enterprise edge servers, or campus edge servers. They operate under tighter resource constraints but provide better proximity to users and may better satisfy local policy constraints.¶

• Local nodes: end devices, customer-premise environments, or lightweight on-premise deployments where limited capabilities may execute when latency, privacy, or data locality requirements dominate.¶

These resources differ in accelerator type, memory capacity, startup overhead, model residency, connectivity, reliability, distance to demand, and trust properties. IDN therefore does not attempt to replicate every capability everywhere. It seeks to place each capability at the level of the hierarchy where it can best balance quality, latency, resource cost, and policy compliance.¶

The model above is compatible with edge-computing discussions in the IETF and IRTF [RFC9556], but IDN focuses on AI inference services and the intelligence-specific metadata required for capability placement, request routing, caching, and trust management.¶

3.3. High-Level Architecture

             +----------------------------------------+
             |        IDN Provider Control Plane      |
             |                                        |
             | +-----------+ +----------+ +---------+ |
             | | Capability| | Resource | | Trust   | |
             | | Registry  | | Broker   | | Manager | |
             | +-----------+ +----------+ +---------+ |
             | +-----------+ +----------+ +---------+ |
             | | Deployment| | Service  | | Cache   | |
             | | Controller| | Router   | | Manager | |
             | +-----------+ +----------+ +---------+ |
             +-------------------+--------------------+
                                 |
            Capability, Resource, State, and Policy Views
                                 |
                   +---------------------------+
                   |   Cloud Data Centers      |
                   |  (General-Purpose Models) |
                   |                           |
                   | - Large foundation        |
                   |     inference models      |
                   | - Capability distillation |
                   +-------------+-------------+
                                 |
                       Capability Distribution
                                 |
             +-------------------+--------------------+
             |                                        |
+------------+-------------+             +------------+-------------+
|    Regional IDN Nodes    |             |    Regional IDN Nodes    |
|(Specialized Capabilities)|             |(Specialized Capabilities)|
|                          |             |                          |
| - Domain-specific models |             |  - Task-oriented models  |
| - Cached popular skills  |             |  - Cached popular skills |
+------------+-------------+             +------------+-------------+
             |                                        |
    Inference|                                        | Inference
    Requests |                                        | Requests
             |                                        |
+------------+-------------+            +-------------+-------------+
|        Edge Nodes        |            |         Edge Nodes        |
|(Lightweight Capabilities)|            | (Lightweight Capabilities)|
|                          |            |                           |
|  - Latency-sensitive     |            |   - Privacy-sensitive     |
|      inference tasks     |            |       inference tasks     |
+------------+-------------+            +-------------+-------------+
             |                                        |
             +-------------------+--------------------+
                                 |
                          +------+------+
                          | Local Nodes |
                          | Limited     |
                          | capabilities|
                          +------+------+
                                 |
                            Clients and
                        Upstream Applications

At a high level, clients or upstream applications issue intelligence requests. The provider control plane uses capability descriptors, resource profiles, state descriptors, and policy information to select an appropriate service instance or execution plan. A plan may use a single node or may involve multiple stages, such as execution of a lightweight capability near the user, fallback to a stronger regional or cloud variant, or reuse of cached state.¶

The six main architectural components are:¶

• Capability registry: stores and advertises intelligence capability descriptors, capability versions, lineage, and policy labels.¶

• Resource broker: integrates compute nodes, aggregates resource profiles, and exposes service-oriented summaries to placement and routing functions.¶

• Deployment controller: decides where capability variants and supporting artifacts should be placed, activated, scaled, migrated, or withdrawn.¶

• Service router: maps each request to a service instance or execution plan using capability, network, compute, state, and policy information.¶

• Cache manager: manages model artifacts, prompt prefixes, tensor state, result objects, and their sharing and invalidation policies.¶

• Trust manager: manages provider-scoped identities, delegations, object authentication, node trust evidence, policy verification, and execution receipts.¶

These components are logically distinct. A deployment may combine them or distribute them across controllers, brokers, site agents, and service meshes.¶

3.4. Intelligence Capability Abstraction

A fundamental challenge for IDN is that the intelligence embodied in a foundation model is not naturally exposed at the right granularity for network delivery. A large model may support many tasks, but treating the entire model checkpoint as the deployment unit makes distribution too coarse-grained. A node would either need to replicate the full checkpoint or forgo the capability entirely.¶

IDN defines an intelligence capability as a bounded and deployable unit of service competence derived from one or more foundation models. A capability does not need to preserve the full generality of the originating model. It may represent the subset of intelligence needed to support a class of requests under explicit quality, latency, security, and resource constraints. Capabilities may be produced through provider-specific mechanisms such as distillation, specialization, compression, adapter-based refinement, quantization, or other optimization techniques. IDN does not mandate a capability extraction method.¶

IDN views capabilities at three levels:¶

• Capability class: a broad function or service category, such as translation, code assistance, visual recognition, or vertical-domain question answering.¶

• Capability variant: a version of a capability class with specific tradeoffs among accuracy, latency, model size, context length, privacy, cost, and trust requirements.¶

• Deployable realization: a concrete implementation of a capability variant, such as a distilled model, quantized model, adapter set, runtime package, or other optimized artifact for a specific hardware or runtime environment.¶

This separation allows the IDN control plane to reason about capability classes and variants while allowing execution platforms to use the concrete realization that best fits their resources. The granularity should be service-effective: small enough to enable differentiated deployment across heterogeneous nodes, but large enough to remain stable, reusable, and meaningful as a service object.¶

3.5. Compute Resource Integration

Distributed compute nodes need to be integrated into IDN as manageable suppliers of execution capability. A compute node joins IDN by registering with a provider controller, broker, or site agent that is responsible for local resource management. Registration creates or updates a resource profile describing static and dynamic properties of the node or site.¶

Resource integration is hierarchical. Fast-changing information such as queueing condition, available accelerator memory, model residency, node health, local connectivity, and recent performance can be collected by local agents. Coarser summaries can then be propagated to higher-level controllers. This approach avoids exposing raw node-level telemetry globally and is compatible with CATS-style abstractions in which traffic steering uses both network and computing state [CATSFramework].¶

A resource profile is service-oriented. It exposes what the node or site can provide to the IDN scheduler, not every hardware detail. For example, a profile may indicate supported accelerator families, memory class, supported inference runtimes, resident models, current load range, locality, jurisdiction, operational policy constraints, and trust evidence.¶

Resource integration is also a trust operation. Before a node hosts sensitive capabilities or serves protected requests, it needs to expose verifiable identity and relevant security properties. The exact attestation or verification mechanism is deployment-specific.¶

3.6. Demand-Driven Capability Deployment

After capabilities have been abstracted and resources have been integrated, IDN determines where each capability should be placed. The objective is not to replicate every capability at every node, but to position each capability where it can best balance demand locality, quality, latency, resource cost, network cost, and policy risk.¶

Deployment can be proactive or reactive. A provider may pre-position a popular capability variant in a region based on expected demand. It may also activate, migrate, scale out, scale back, or withdraw a capability as demand and resource conditions change. When a recurring task pattern becomes frequent in a region, the provider may derive or select a compact specialization and deploy it to suitable regional or edge nodes. When demand subsides, the provider may remove it to recover constrained resources.¶

A deployment decision considers at least the following inputs:¶

• demand locality and predicted reuse;¶

• capability quality tier and resource requirement;¶

• model artifact size, loading cost, initialization cost, and memory footprint;¶

• node capacity, current load, reliability, and locality;¶

• network transfer, backhaul, and egress cost;¶

• privacy, jurisdiction, isolation, and trust constraints; and¶

• rollback, version compatibility, and operational safety requirements.¶

Deployment is a closed-loop process. Demand surges, resource failures, model updates, policy changes, and security events can invalidate a previously effective placement. IDN therefore needs mechanisms for controlled rollout, rollback, version coexistence, and deprecation.¶

3.7. Capability-Aware Service Routing

Once capabilities are deployed, IDN needs to determine how each incoming request should be served. Service routing in IDN selects an execution location, a capability variant, and an execution context. The selected plan may be a single service instance or a multi-stage path across service instances.¶

An IDN service instance is a reachable execution endpoint that provides an IDN service or part of an IDN service. It is hosted on a compute node and implements one or more deployable realizations. Multiple service instances may provide the same capability variant with different locality, load, trust, state, and cost properties.¶

A request may specify the requested capability explicitly, or the provider may infer it from application context. It may also include quality targets, response-time requirements, privacy or locality constraints, state-affinity information, tenant information, and cost or resource preferences. The service router constructs the feasible set of service instances or execution plans that satisfy the request constraints and selects among them according to service policy.¶

Relevant routing inputs include:¶

• network path latency, loss, congestion, and locality;¶

• queueing delay, available accelerator memory, model residency, and expected execution time;¶

• capability quality tier, context limit, and compatibility;¶

• state availability, state transfer cost, and state-affinity value;¶

• loading or warm-up cost for non-resident capabilities;¶

• policy constraints, isolation requirements, and trust evidence; and¶

• load-balancing, admission-control, and cost policies.¶

The closest node is not always the best node. A nearby edge node may lack the requested capability, may be overloaded, may not hold reusable state, or may not satisfy a policy constraint. Conversely, a more distant regional node may hold a warm service instance or reusable state that provides lower end-to-end delay. IDN routing is therefore a service-quality control loop rather than only a path-selection mechanism.¶

State-awareness is especially important for LLM serving. Interactive sessions, long-context inference, and split execution can accumulate prompt prefixes, KV caches, retrieved context, embeddings, and other intermediate state. Moving, reconstructing, or discarding such state can dominate the latency gain from choosing a shorter network path. Existing LLM-serving work has shown that memory management and KV-cache handling materially affect latency and throughput [PagedAttention].¶

3.8. State-Aware Caching and Reuse

Caching is essential for improving the efficiency and service quality of distributed inference, but IDN caching is broader than conventional content caching. IDN treats caching as state management: the system decides what state should be cached, where it should be placed, how it may be shared, when it should be migrated, and when it should be invalidated.¶

IDN distinguishes four classes of cacheable objects:¶

• Artifact caches: stable deployment objects such as model weights, adapters, quantized variants, tokenizers, safety components, and runtime packages.¶

• Prefix caches: reusable prompt modules, system instructions, retrieved-context templates, or other common input prefixes.¶

• Tensor-state caches: intermediate execution state such as KV caches or other activations that can accelerate later inference.¶

• Result caches: reusable outputs for identical or semantically equivalent inputs under compatible model, decoding, and policy settings. Result caches can also include deterministic subcomputations such as embeddings, retrieval outputs, or tool results.¶

Object type is separate from sharing scope. A cached object may be public, tenant-shared, session-private, user-private, or hardware-bound. The sharing scope affects cache admission, routing, access control, encryption, and eviction.¶

To enable cached objects to be discovered and managed across dynamic deployments, IDN uses stable names or descriptors rather than only the address of the node that currently stores the object. This follows the ICN principle of decoupling object identity from object location [NDN]. However, IDN does not make location irrelevant. The control plane needs to resolve each named object to one or more valid copies and decide whether to route a request to a node that already holds the object, migrate the object, recompute it, or fall back to a remote execution plan.¶

Cache usefulness depends on predicted reuse, latency reduction, state transfer cost, storage cost, privacy cost, compatibility, and future routing decisions. Techniques for prompt reuse, KV-cache compression, and multi-tenant KV-cache reuse provide examples of the types of state that may be useful in IDN, but the IDN architecture does not mandate a specific cache implementation [PromptCache] [CacheGen] [KVShare].¶

3.9. Model Evolution and Lifecycle

Inference capabilities within an IDN are expected to evolve over time. Models may be updated, replaced, refined, or specialized as new data becomes available, as usage patterns change, or as application requirements evolve. The framework supports incremental updates and the coexistence of multiple capability versions, enabling gradual transitions rather than requiring global or disruptive replacements.¶

Model evolution may be driven by multiple sources. Updates can be produced centrally, for example through cloud-side retraining, refinement, or distillation of models, and subsequently distributed to appropriate locations within the IDN. In addition, where permitted by policy and regulatory constraints, inference capabilities deployed at edge or near-user locations may be locally adapted using user-provided or locally observed data. Such local adaptation may follow federated or privacy-preserving learning approaches, in which locally derived updates contribute to global model improvement without requiring raw data to leave the local environment.¶

Lifecycle management of inference capabilities includes deployment, update, versioning, deprecation, and removal. Different versions of a capability may coexist at the same or different locations, allowing the framework to balance stability, performance, and innovation. While this document does not specify how lifecycle management processes are implemented, it assumes that mechanisms for controlled rollout, compatibility management, and rollback are necessary to ensure operational stability and consistency within an IDN.¶

5.1. Data Privacy and Locality

Inference requests often include user, enterprise, sensor, or application data. Such data may be sensitive or regulated. IDN can reduce unnecessary data movement by enabling selected inference tasks to execute closer to the data source, but it also increases the number of places where data may be processed.¶

Privacy and locality requirements therefore need to be represented as scheduling and routing constraints. A request may require execution within a particular site, jurisdiction, tenant boundary, or isolation domain. A request may also prohibit sharing or caching of derived state. These constraints influence capability placement, service routing, cache admission, and object reuse.¶

5.2. Model Integrity and Authenticity

IDN relies on model artifacts, adapters, runtime packages, cached state, and result objects that may be distributed and reused. A tampered or unauthorized object could produce incorrect, unsafe, or policy-violating output. IDN deployments therefore need mechanisms to verify that a capability, model artifact, state object, or execution receipt corresponds to an authorized version and originates from an authorized producer.¶

Architectural hooks include signed capability descriptors, object signatures, compatibility hashes, authenticated metadata, provenance records, policy labels, controlled rollout, invalidation, and rollback. These hooks are especially important for reusable state because caches and routers should not have to trust a storage location merely because it holds an object.¶

5.3. Provider-Scoped Trust and Delegation

The deployment assumption in this document is a provider-controlled environment. Under this assumption, the trust infrastructure can be scoped to the provider domain rather than relying on a global certification hierarchy. SDSI provides one relevant design principle: principals can be represented by public keys, local names and groups can express authorization, and signed certificates can delegate restricted authority [SDSI].¶

An IDN provider can use a provider root key as a trust anchor and delegate authority to regional controllers, site agents, service runtimes, or object-producing components. Verification of a capability descriptor, state object, or execution receipt can then trace signed metadata through a delegation chain back to the provider root. Each delegation can restrict what the delegated principal is allowed to sign, update, host, or authorize.¶

The exact key-management, revocation, rotation, and audit mechanisms are deployment-specific and are not specified by this document.¶

5.4. Trust Schema and Object Authentication

Trust Schema in NDN provides a useful design principle for IDN object authentication: name patterns can specify which keys are authorized to sign which classes of objects [TrustSchema]. IDN can use an analogous schema to define which provider component, capability version, runtime, or site agent may create, sign, update, or consume each class of IDN object.¶

Stable object names provide a common handle for integrity, access control, encryption metadata, provenance, and audit independent of the node that currently stores the object. Objects containing private context or tenant-specific state should be encrypted according to the applicable policy. Signatures and authenticated metadata can allow caches, routers, and auditors to verify integrity and policy eligibility without trusting the storage location itself.¶

5.5. Node Trust and Execution Evidence

A compute node that advertises resources should expose verifiable identity and policy-relevant properties before serving protected requests or hosting sensitive capabilities. Depending on deployment requirements, such evidence may include node identity, software version, runtime configuration, isolation properties, trusted execution evidence, or other attestation results.¶

Execution receipts can record capability versions, node attestations, object signatures, delegation evidence, schema-based policy verdicts, cache usage, and routing or deployment decisions. These receipts support debugging, accounting, compliance checks, and incident response. They do not by themselves prove semantic correctness of inference results.¶

5.6. Reuse, Isolation, and Information Leakage

State-aware caching and reuse can improve scalability and latency, but reuse across users, tenants, sessions, or hardware environments can introduce information leakage. IDN deployments need to enforce sharing scope, access policy, encryption policy, eviction policy, and compatibility constraints before reusing cached objects.¶

Public or tenant-shared objects may be reusable across multiple requests. Session-private or user-private objects require stronger isolation. Hardware-bound objects may be unusable after migration. Result objects may only be safe to reuse when model version, decoding configuration, prompt normalization, policy labels, and input equivalence rules are compatible.¶

5.7. Availability and Abuse Considerations

Popular capabilities and cached state can become high-value targets for denial-of-service or abuse. A request-routing policy that overemphasizes locality or state affinity may create hotspots. IDN deployments therefore need resilience mechanisms such as load-aware routing, admission control, capability replication, fallback to compatible variants, early rejection under overload, failure detection, and rollback of unsafe components.¶

Security events can also require rapid invalidation of model artifacts, cached state, or capability descriptors. The architecture should support object invalidation and service rerouting without requiring global redeployment.¶